--- /dev/null
- Fatal("%v escapes to heap, not allowed in runtime.", n)
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gc
+
+import (
+ "bytes"
+ "fmt"
+ "html"
+ "math"
+ "os"
+ "strings"
+
+ "cmd/compile/internal/ssa"
+ "cmd/internal/obj"
+ "cmd/internal/obj/x86"
+)
+
+// buildssa builds an SSA function
+// and reports whether it should be used.
+// Once the SSA implementation is complete,
+// it will never return nil, and the bool can be removed.
+func buildssa(fn *Node) (ssafn *ssa.Func, usessa bool) {
+ name := fn.Func.Nname.Sym.Name
+ usessa = strings.HasSuffix(name, "_ssa") || name == os.Getenv("GOSSAFUNC")
+
+ if usessa {
+ fmt.Println("generating SSA for", name)
+ dumplist("buildssa-enter", fn.Func.Enter)
+ dumplist("buildssa-body", fn.Nbody)
+ }
+
+ var s state
+ s.pushLine(fn.Lineno)
+ defer s.popLine()
+
+ // TODO(khr): build config just once at the start of the compiler binary
+
+ var e ssaExport
+ e.log = usessa
+ s.config = ssa.NewConfig(Thearch.Thestring, &e)
+ s.f = s.config.NewFunc()
+ s.f.Name = name
+
+ if name == os.Getenv("GOSSAFUNC") {
+ // TODO: tempfile? it is handy to have the location
+ // of this file be stable, so you can just reload in the browser.
+ s.config.HTML = ssa.NewHTMLWriter("ssa.html", &s, name)
+ // TODO: generate and print a mapping from nodes to values and blocks
+ }
+ defer func() {
+ if !usessa {
+ s.config.HTML.Close()
+ }
+ }()
+
+ // If SSA support for the function is incomplete,
+ // assume that any panics are due to violated
+ // invariants. Swallow them silently.
+ defer func() {
+ if err := recover(); err != nil {
+ if !e.unimplemented {
+ panic(err)
+ }
+ }
+ }()
+
+ // We construct SSA using an algorithm similar to
+ // Brau, Buchwald, Hack, Leißa, Mallon, and Zwinkau
+ // http://pp.info.uni-karlsruhe.de/uploads/publikationen/braun13cc.pdf
+ // TODO: check this comment
+
+ // Allocate starting block
+ s.f.Entry = s.f.NewBlock(ssa.BlockPlain)
+
+ // Allocate exit block
+ s.exit = s.f.NewBlock(ssa.BlockExit)
+
+ // Allocate starting values
+ s.vars = map[*Node]*ssa.Value{}
+ s.labels = map[string]*ssaLabel{}
+ s.labeledNodes = map[*Node]*ssaLabel{}
+ s.startmem = s.entryNewValue0(ssa.OpArg, ssa.TypeMem)
+ s.sp = s.entryNewValue0(ssa.OpSP, Types[TUINTPTR]) // TODO: use generic pointer type (unsafe.Pointer?) instead
+ s.sb = s.entryNewValue0(ssa.OpSB, Types[TUINTPTR])
+
+ // Generate addresses of local declarations
+ s.decladdrs = map[*Node]*ssa.Value{}
+ for d := fn.Func.Dcl; d != nil; d = d.Next {
+ n := d.N
+ switch n.Class {
+ case PPARAM, PPARAMOUT:
+ aux := &ssa.ArgSymbol{Typ: n.Type, Node: n}
+ s.decladdrs[n] = s.entryNewValue1A(ssa.OpAddr, Ptrto(n.Type), aux, s.sp)
+ case PAUTO:
+ // processed at each use, to prevent Addr coming
+ // before the decl.
+ case PFUNC:
+ // local function - already handled by frontend
+ default:
+ str := ""
+ if n.Class&PHEAP != 0 {
+ str = ",heap"
+ }
+ s.Unimplementedf("local variable with class %s%s unimplemented", classnames[n.Class&^PHEAP], str)
+ }
+ }
+ // nodfp is a special argument which is the function's FP.
+ aux := &ssa.ArgSymbol{Typ: Types[TUINTPTR], Node: nodfp}
+ s.decladdrs[nodfp] = s.entryNewValue1A(ssa.OpAddr, Types[TUINTPTR], aux, s.sp)
+
+ // Convert the AST-based IR to the SSA-based IR
+ s.startBlock(s.f.Entry)
+ s.stmtList(fn.Func.Enter)
+ s.stmtList(fn.Nbody)
+
+ // fallthrough to exit
+ if b := s.endBlock(); b != nil {
+ b.Kind = ssa.BlockRet
+ b.AddEdgeTo(s.exit)
+ }
+
+ // Finish up exit block
+ s.startBlock(s.exit)
+ s.exit.Control = s.mem()
+ s.endBlock()
+
+ // Check that we used all labels
+ for name, lab := range s.labels {
+ if !lab.used() && !lab.reported {
+ yyerrorl(int(lab.defNode.Lineno), "label %v defined and not used", name)
+ lab.reported = true
+ }
+ if lab.used() && !lab.defined() && !lab.reported {
+ yyerrorl(int(lab.useNode.Lineno), "label %v not defined", name)
+ lab.reported = true
+ }
+ }
+
+ // Check any forward gotos. Non-forward gotos have already been checked.
+ for _, n := range s.fwdGotos {
+ lab := s.labels[n.Left.Sym.Name]
+ // If the label is undefined, we have already have printed an error.
+ if lab.defined() {
+ s.checkgoto(n, lab.defNode)
+ }
+ }
+
+ if nerrors > 0 {
+ return nil, false
+ }
+
+ // Link up variable uses to variable definitions
+ s.linkForwardReferences()
+
+ // Main call to ssa package to compile function
+ ssa.Compile(s.f)
+
+ // Calculate stats about what percentage of functions SSA handles.
+ if false {
+ fmt.Printf("SSA implemented: %t\n", !e.unimplemented)
+ }
+
+ if e.unimplemented {
+ return nil, false
+ }
+
+ // TODO: enable codegen more broadly once the codegen stabilizes
+ // and runtime support is in (gc maps, write barriers, etc.)
+ return s.f, usessa || localpkg.Name == os.Getenv("GOSSAPKG")
+}
+
+type state struct {
+ // configuration (arch) information
+ config *ssa.Config
+
+ // function we're building
+ f *ssa.Func
+
+ // exit block that "return" jumps to (and panics jump to)
+ exit *ssa.Block
+
+ // labels and labeled control flow nodes (OFOR, OSWITCH, OSELECT) in f
+ labels map[string]*ssaLabel
+ labeledNodes map[*Node]*ssaLabel
+
+ // gotos that jump forward; required for deferred checkgoto calls
+ fwdGotos []*Node
+
+ // unlabeled break and continue statement tracking
+ breakTo *ssa.Block // current target for plain break statement
+ continueTo *ssa.Block // current target for plain continue statement
+
+ // current location where we're interpreting the AST
+ curBlock *ssa.Block
+
+ // variable assignments in the current block (map from variable symbol to ssa value)
+ // *Node is the unique identifier (an ONAME Node) for the variable.
+ vars map[*Node]*ssa.Value
+
+ // all defined variables at the end of each block. Indexed by block ID.
+ defvars []map[*Node]*ssa.Value
+
+ // addresses of PPARAM and PPARAMOUT variables.
+ decladdrs map[*Node]*ssa.Value
+
+ // starting values. Memory, frame pointer, and stack pointer
+ startmem *ssa.Value
+ sp *ssa.Value
+ sb *ssa.Value
+
+ // line number stack. The current line number is top of stack
+ line []int32
+}
+
+type ssaLabel struct {
+ target *ssa.Block // block identified by this label
+ breakTarget *ssa.Block // block to break to in control flow node identified by this label
+ continueTarget *ssa.Block // block to continue to in control flow node identified by this label
+ defNode *Node // label definition Node (OLABEL)
+ // Label use Node (OGOTO, OBREAK, OCONTINUE).
+ // Used only for error detection and reporting.
+ // There might be multiple uses, but we only need to track one.
+ useNode *Node
+ reported bool // reported indicates whether an error has already been reported for this label
+}
+
+// defined reports whether the label has a definition (OLABEL node).
+func (l *ssaLabel) defined() bool { return l.defNode != nil }
+
+// used reports whether the label has a use (OGOTO, OBREAK, or OCONTINUE node).
+func (l *ssaLabel) used() bool { return l.useNode != nil }
+
+// label returns the label associated with sym, creating it if necessary.
+func (s *state) label(sym *Sym) *ssaLabel {
+ lab := s.labels[sym.Name]
+ if lab == nil {
+ lab = new(ssaLabel)
+ s.labels[sym.Name] = lab
+ }
+ return lab
+}
+
+func (s *state) Logf(msg string, args ...interface{}) { s.config.Logf(msg, args...) }
+func (s *state) Fatalf(msg string, args ...interface{}) { s.config.Fatalf(msg, args...) }
+func (s *state) Unimplementedf(msg string, args ...interface{}) { s.config.Unimplementedf(msg, args...) }
+
+// dummy node for the memory variable
+var memvar = Node{Op: ONAME, Sym: &Sym{Name: "mem"}}
+
+// startBlock sets the current block we're generating code in to b.
+func (s *state) startBlock(b *ssa.Block) {
+ if s.curBlock != nil {
+ s.Fatalf("starting block %v when block %v has not ended", b, s.curBlock)
+ }
+ s.curBlock = b
+ s.vars = map[*Node]*ssa.Value{}
+}
+
+// endBlock marks the end of generating code for the current block.
+// Returns the (former) current block. Returns nil if there is no current
+// block, i.e. if no code flows to the current execution point.
+func (s *state) endBlock() *ssa.Block {
+ b := s.curBlock
+ if b == nil {
+ return nil
+ }
+ for len(s.defvars) <= int(b.ID) {
+ s.defvars = append(s.defvars, nil)
+ }
+ s.defvars[b.ID] = s.vars
+ s.curBlock = nil
+ s.vars = nil
+ b.Line = s.peekLine()
+ return b
+}
+
+// pushLine pushes a line number on the line number stack.
+func (s *state) pushLine(line int32) {
+ s.line = append(s.line, line)
+}
+
+// popLine pops the top of the line number stack.
+func (s *state) popLine() {
+ s.line = s.line[:len(s.line)-1]
+}
+
+// peekLine peek the top of the line number stack.
+func (s *state) peekLine() int32 {
+ return s.line[len(s.line)-1]
+}
+
+func (s *state) Error(msg string, args ...interface{}) {
+ yyerrorl(int(s.peekLine()), msg, args...)
+}
+
+// newValue0 adds a new value with no arguments to the current block.
+func (s *state) newValue0(op ssa.Op, t ssa.Type) *ssa.Value {
+ return s.curBlock.NewValue0(s.peekLine(), op, t)
+}
+
+// newValue0A adds a new value with no arguments and an aux value to the current block.
+func (s *state) newValue0A(op ssa.Op, t ssa.Type, aux interface{}) *ssa.Value {
+ return s.curBlock.NewValue0A(s.peekLine(), op, t, aux)
+}
+
+// newValue0I adds a new value with no arguments and an auxint value to the current block.
+func (s *state) newValue0I(op ssa.Op, t ssa.Type, auxint int64) *ssa.Value {
+ return s.curBlock.NewValue0I(s.peekLine(), op, t, auxint)
+}
+
+// newValue1 adds a new value with one argument to the current block.
+func (s *state) newValue1(op ssa.Op, t ssa.Type, arg *ssa.Value) *ssa.Value {
+ return s.curBlock.NewValue1(s.peekLine(), op, t, arg)
+}
+
+// newValue1A adds a new value with one argument and an aux value to the current block.
+func (s *state) newValue1A(op ssa.Op, t ssa.Type, aux interface{}, arg *ssa.Value) *ssa.Value {
+ return s.curBlock.NewValue1A(s.peekLine(), op, t, aux, arg)
+}
+
+// newValue1I adds a new value with one argument and an auxint value to the current block.
+func (s *state) newValue1I(op ssa.Op, t ssa.Type, aux int64, arg *ssa.Value) *ssa.Value {
+ return s.curBlock.NewValue1I(s.peekLine(), op, t, aux, arg)
+}
+
+// newValue2 adds a new value with two arguments to the current block.
+func (s *state) newValue2(op ssa.Op, t ssa.Type, arg0, arg1 *ssa.Value) *ssa.Value {
+ return s.curBlock.NewValue2(s.peekLine(), op, t, arg0, arg1)
+}
+
+// newValue2I adds a new value with two arguments and an auxint value to the current block.
+func (s *state) newValue2I(op ssa.Op, t ssa.Type, aux int64, arg0, arg1 *ssa.Value) *ssa.Value {
+ return s.curBlock.NewValue2I(s.peekLine(), op, t, aux, arg0, arg1)
+}
+
+// newValue3 adds a new value with three arguments to the current block.
+func (s *state) newValue3(op ssa.Op, t ssa.Type, arg0, arg1, arg2 *ssa.Value) *ssa.Value {
+ return s.curBlock.NewValue3(s.peekLine(), op, t, arg0, arg1, arg2)
+}
+
+// newValue3I adds a new value with three arguments and an auxint value to the current block.
+func (s *state) newValue3I(op ssa.Op, t ssa.Type, aux int64, arg0, arg1, arg2 *ssa.Value) *ssa.Value {
+ return s.curBlock.NewValue3I(s.peekLine(), op, t, aux, arg0, arg1, arg2)
+}
+
+// entryNewValue0 adds a new value with no arguments to the entry block.
+func (s *state) entryNewValue0(op ssa.Op, t ssa.Type) *ssa.Value {
+ return s.f.Entry.NewValue0(s.peekLine(), op, t)
+}
+
+// entryNewValue0A adds a new value with no arguments and an aux value to the entry block.
+func (s *state) entryNewValue0A(op ssa.Op, t ssa.Type, aux interface{}) *ssa.Value {
+ return s.f.Entry.NewValue0A(s.peekLine(), op, t, aux)
+}
+
+// entryNewValue0I adds a new value with no arguments and an auxint value to the entry block.
+func (s *state) entryNewValue0I(op ssa.Op, t ssa.Type, auxint int64) *ssa.Value {
+ return s.f.Entry.NewValue0I(s.peekLine(), op, t, auxint)
+}
+
+// entryNewValue1 adds a new value with one argument to the entry block.
+func (s *state) entryNewValue1(op ssa.Op, t ssa.Type, arg *ssa.Value) *ssa.Value {
+ return s.f.Entry.NewValue1(s.peekLine(), op, t, arg)
+}
+
+// entryNewValue1 adds a new value with one argument and an auxint value to the entry block.
+func (s *state) entryNewValue1I(op ssa.Op, t ssa.Type, auxint int64, arg *ssa.Value) *ssa.Value {
+ return s.f.Entry.NewValue1I(s.peekLine(), op, t, auxint, arg)
+}
+
+// entryNewValue1A adds a new value with one argument and an aux value to the entry block.
+func (s *state) entryNewValue1A(op ssa.Op, t ssa.Type, aux interface{}, arg *ssa.Value) *ssa.Value {
+ return s.f.Entry.NewValue1A(s.peekLine(), op, t, aux, arg)
+}
+
+// entryNewValue2 adds a new value with two arguments to the entry block.
+func (s *state) entryNewValue2(op ssa.Op, t ssa.Type, arg0, arg1 *ssa.Value) *ssa.Value {
+ return s.f.Entry.NewValue2(s.peekLine(), op, t, arg0, arg1)
+}
+
+// constInt* routines add a new const int value to the entry block.
+func (s *state) constInt8(t ssa.Type, c int8) *ssa.Value {
+ return s.f.ConstInt8(s.peekLine(), t, c)
+}
+func (s *state) constInt16(t ssa.Type, c int16) *ssa.Value {
+ return s.f.ConstInt16(s.peekLine(), t, c)
+}
+func (s *state) constInt32(t ssa.Type, c int32) *ssa.Value {
+ return s.f.ConstInt32(s.peekLine(), t, c)
+}
+func (s *state) constInt64(t ssa.Type, c int64) *ssa.Value {
+ return s.f.ConstInt64(s.peekLine(), t, c)
+}
+func (s *state) constFloat32(t ssa.Type, c float64) *ssa.Value {
+ return s.f.ConstFloat32(s.peekLine(), t, c)
+}
+func (s *state) constFloat64(t ssa.Type, c float64) *ssa.Value {
+ return s.f.ConstFloat64(s.peekLine(), t, c)
+}
+func (s *state) constIntPtr(t ssa.Type, c int64) *ssa.Value {
+ if s.config.PtrSize == 4 && int64(int32(c)) != c {
+ s.Fatalf("pointer constant too big %d", c)
+ }
+ return s.f.ConstIntPtr(s.peekLine(), t, c)
+}
+func (s *state) constInt(t ssa.Type, c int64) *ssa.Value {
+ if s.config.IntSize == 8 {
+ return s.constInt64(t, c)
+ }
+ if int64(int32(c)) != c {
+ s.Fatalf("integer constant too big %d", c)
+ }
+ return s.constInt32(t, int32(c))
+}
+
+// ssaStmtList converts the statement n to SSA and adds it to s.
+func (s *state) stmtList(l *NodeList) {
+ for ; l != nil; l = l.Next {
+ s.stmt(l.N)
+ }
+}
+
+// ssaStmt converts the statement n to SSA and adds it to s.
+func (s *state) stmt(n *Node) {
+ s.pushLine(n.Lineno)
+ defer s.popLine()
+
+ // If s.curBlock is nil, then we're about to generate dead code.
+ // We can't just short-circuit here, though,
+ // because we check labels and gotos as part of SSA generation.
+ // Provide a block for the dead code so that we don't have
+ // to add special cases everywhere else.
+ if s.curBlock == nil {
+ dead := s.f.NewBlock(ssa.BlockPlain)
+ s.startBlock(dead)
+ }
+
+ s.stmtList(n.Ninit)
+ switch n.Op {
+
+ case OBLOCK:
+ s.stmtList(n.List)
+
+ // No-ops
+ case OEMPTY, ODCLCONST, ODCLTYPE, OFALL:
+
+ // Expression statements
+ case OCALLFUNC, OCALLMETH, OCALLINTER:
+ s.expr(n)
+
+ case ODCL:
+ if n.Left.Class&PHEAP == 0 {
+ return
+ }
+ if compiling_runtime != 0 {
- Fatal("OCALLMETH: n.Left not an ODOTMETH: %v", left)
++ Fatalf("%v escapes to heap, not allowed in runtime.", n)
+ }
+
+ // TODO: the old pass hides the details of PHEAP
+ // variables behind ONAME nodes. Figure out if it's better
+ // to rewrite the tree and make the heapaddr construct explicit
+ // or to keep this detail hidden behind the scenes.
+ palloc := prealloc[n.Left]
+ if palloc == nil {
+ palloc = callnew(n.Left.Type)
+ prealloc[n.Left] = palloc
+ }
+ s.assign(OAS, n.Left.Name.Heapaddr, palloc)
+
+ case OLABEL:
+ sym := n.Left.Sym
+
+ if isblanksym(sym) {
+ // Empty identifier is valid but useless.
+ // See issues 11589, 11593.
+ return
+ }
+
+ lab := s.label(sym)
+
+ // Associate label with its control flow node, if any
+ if ctl := n.Name.Defn; ctl != nil {
+ switch ctl.Op {
+ case OFOR, OSWITCH, OSELECT:
+ s.labeledNodes[ctl] = lab
+ }
+ }
+
+ if !lab.defined() {
+ lab.defNode = n
+ } else {
+ s.Error("label %v already defined at %v", sym, Ctxt.Line(int(lab.defNode.Lineno)))
+ lab.reported = true
+ }
+ // The label might already have a target block via a goto.
+ if lab.target == nil {
+ lab.target = s.f.NewBlock(ssa.BlockPlain)
+ }
+
+ // go to that label (we pretend "label:" is preceded by "goto label")
+ b := s.endBlock()
+ b.AddEdgeTo(lab.target)
+ s.startBlock(lab.target)
+
+ case OGOTO:
+ sym := n.Left.Sym
+
+ lab := s.label(sym)
+ if lab.target == nil {
+ lab.target = s.f.NewBlock(ssa.BlockPlain)
+ }
+ if !lab.used() {
+ lab.useNode = n
+ }
+
+ if lab.defined() {
+ s.checkgoto(n, lab.defNode)
+ } else {
+ s.fwdGotos = append(s.fwdGotos, n)
+ }
+
+ b := s.endBlock()
+ b.AddEdgeTo(lab.target)
+
+ case OAS, OASWB:
+ // Check whether we can generate static data rather than code.
+ // If so, ignore n and defer data generation until codegen.
+ // Failure to do this causes writes to readonly symbols.
+ if gen_as_init(n, true) {
+ var data []*Node
+ if s.f.StaticData != nil {
+ data = s.f.StaticData.([]*Node)
+ }
+ s.f.StaticData = append(data, n)
+ return
+ }
+ s.assign(n.Op, n.Left, n.Right)
+
+ case OIF:
+ cond := s.expr(n.Left)
+ b := s.endBlock()
+ b.Kind = ssa.BlockIf
+ b.Control = cond
+ b.Likely = ssa.BranchPrediction(n.Likely) // gc and ssa both use -1/0/+1 for likeliness
+
+ bThen := s.f.NewBlock(ssa.BlockPlain)
+ bEnd := s.f.NewBlock(ssa.BlockPlain)
+ var bElse *ssa.Block
+
+ if n.Rlist == nil {
+ b.AddEdgeTo(bThen)
+ b.AddEdgeTo(bEnd)
+ } else {
+ bElse = s.f.NewBlock(ssa.BlockPlain)
+ b.AddEdgeTo(bThen)
+ b.AddEdgeTo(bElse)
+ }
+
+ s.startBlock(bThen)
+ s.stmtList(n.Nbody)
+ if b := s.endBlock(); b != nil {
+ b.AddEdgeTo(bEnd)
+ }
+
+ if n.Rlist != nil {
+ s.startBlock(bElse)
+ s.stmtList(n.Rlist)
+ if b := s.endBlock(); b != nil {
+ b.AddEdgeTo(bEnd)
+ }
+ }
+ s.startBlock(bEnd)
+
+ case ORETURN:
+ s.stmtList(n.List)
+ b := s.endBlock()
+ b.Kind = ssa.BlockRet
+ b.AddEdgeTo(s.exit)
+
+ case OCONTINUE, OBREAK:
+ var op string
+ var to *ssa.Block
+ switch n.Op {
+ case OCONTINUE:
+ op = "continue"
+ to = s.continueTo
+ case OBREAK:
+ op = "break"
+ to = s.breakTo
+ }
+ if n.Left == nil {
+ // plain break/continue
+ if to == nil {
+ s.Error("%s is not in a loop", op)
+ return
+ }
+ // nothing to do; "to" is already the correct target
+ } else {
+ // labeled break/continue; look up the target
+ sym := n.Left.Sym
+ lab := s.label(sym)
+ if !lab.used() {
+ lab.useNode = n.Left
+ }
+ if !lab.defined() {
+ s.Error("%s label not defined: %v", op, sym)
+ lab.reported = true
+ return
+ }
+ switch n.Op {
+ case OCONTINUE:
+ to = lab.continueTarget
+ case OBREAK:
+ to = lab.breakTarget
+ }
+ if to == nil {
+ // Valid label but not usable with a break/continue here, e.g.:
+ // for {
+ // continue abc
+ // }
+ // abc:
+ // for {}
+ s.Error("invalid %s label %v", op, sym)
+ lab.reported = true
+ return
+ }
+ }
+
+ b := s.endBlock()
+ b.AddEdgeTo(to)
+
+ case OFOR:
+ // OFOR: for Ninit; Left; Right { Nbody }
+ bCond := s.f.NewBlock(ssa.BlockPlain)
+ bBody := s.f.NewBlock(ssa.BlockPlain)
+ bIncr := s.f.NewBlock(ssa.BlockPlain)
+ bEnd := s.f.NewBlock(ssa.BlockPlain)
+
+ // first, jump to condition test
+ b := s.endBlock()
+ b.AddEdgeTo(bCond)
+
+ // generate code to test condition
+ s.startBlock(bCond)
+ var cond *ssa.Value
+ if n.Left != nil {
+ cond = s.expr(n.Left)
+ } else {
+ cond = s.entryNewValue0I(ssa.OpConstBool, Types[TBOOL], 1) // 1 = true
+ }
+ b = s.endBlock()
+ b.Kind = ssa.BlockIf
+ b.Control = cond
+ b.Likely = ssa.BranchLikely
+ b.AddEdgeTo(bBody)
+ b.AddEdgeTo(bEnd)
+
+ // set up for continue/break in body
+ prevContinue := s.continueTo
+ prevBreak := s.breakTo
+ s.continueTo = bIncr
+ s.breakTo = bEnd
+ lab := s.labeledNodes[n]
+ if lab != nil {
+ // labeled for loop
+ lab.continueTarget = bIncr
+ lab.breakTarget = bEnd
+ }
+
+ // generate body
+ s.startBlock(bBody)
+ s.stmtList(n.Nbody)
+
+ // tear down continue/break
+ s.continueTo = prevContinue
+ s.breakTo = prevBreak
+ if lab != nil {
+ lab.continueTarget = nil
+ lab.breakTarget = nil
+ }
+
+ // done with body, goto incr
+ if b := s.endBlock(); b != nil {
+ b.AddEdgeTo(bIncr)
+ }
+
+ // generate incr
+ s.startBlock(bIncr)
+ if n.Right != nil {
+ s.stmt(n.Right)
+ }
+ if b := s.endBlock(); b != nil {
+ b.AddEdgeTo(bCond)
+ }
+ s.startBlock(bEnd)
+
+ case OSWITCH, OSELECT:
+ // These have been mostly rewritten by the front end into their Nbody fields.
+ // Our main task is to correctly hook up any break statements.
+ bEnd := s.f.NewBlock(ssa.BlockPlain)
+
+ prevBreak := s.breakTo
+ s.breakTo = bEnd
+ lab := s.labeledNodes[n]
+ if lab != nil {
+ // labeled
+ lab.breakTarget = bEnd
+ }
+
+ // generate body code
+ s.stmtList(n.Nbody)
+
+ s.breakTo = prevBreak
+ if lab != nil {
+ lab.breakTarget = nil
+ }
+
+ if b := s.endBlock(); b != nil {
+ b.AddEdgeTo(bEnd)
+ }
+ s.startBlock(bEnd)
+
+ case OVARKILL:
+ // Insert a varkill op to record that a variable is no longer live.
+ // We only care about liveness info at call sites, so putting the
+ // varkill in the store chain is enough to keep it correctly ordered
+ // with respect to call ops.
+ s.vars[&memvar] = s.newValue1A(ssa.OpVarKill, ssa.TypeMem, n.Left, s.mem())
+
+ case OPROC, ODEFER:
+ call := n.Left
+ fn := call.Left
+ if call.Op != OCALLFUNC {
+ s.Unimplementedf("defer/go of %s", opnames[call.Op])
+ }
+
+ // Write argsize and closure (args to Newproc/Deferproc)
+ argsize := s.constInt32(Types[TUINT32], int32(fn.Type.Argwid))
+ s.vars[&memvar] = s.newValue3I(ssa.OpStore, ssa.TypeMem, 4, s.sp, argsize, s.mem())
+ closure := s.expr(fn)
+ addr := s.entryNewValue1I(ssa.OpOffPtr, Ptrto(Types[TUINTPTR]), int64(Widthptr), s.sp)
+ s.vars[&memvar] = s.newValue3I(ssa.OpStore, ssa.TypeMem, int64(Widthptr), addr, closure, s.mem())
+
+ // Run all argument assignments. The arg slots have already
+ // been offset by 2*widthptr.
+ s.stmtList(call.List)
+
+ // Call deferproc or newproc
+ bNext := s.f.NewBlock(ssa.BlockPlain)
+ var op ssa.Op
+ switch n.Op {
+ case ODEFER:
+ op = ssa.OpDeferCall
+ case OPROC:
+ op = ssa.OpGoCall
+ }
+ r := s.newValue1(op, ssa.TypeMem, s.mem())
+ r.AuxInt = fn.Type.Argwid + 2*int64(Widthptr) // total stack space used
+ s.vars[&memvar] = r
+ b := s.endBlock()
+ b.Kind = ssa.BlockCall
+ b.Control = r
+ b.AddEdgeTo(bNext)
+ b.AddEdgeTo(s.exit)
+ s.startBlock(bNext)
+
+ default:
+ s.Unimplementedf("unhandled stmt %s", opnames[n.Op])
+ }
+}
+
+type opAndType struct {
+ op uint8
+ etype uint8
+}
+
+var opToSSA = map[opAndType]ssa.Op{
+ opAndType{OADD, TINT8}: ssa.OpAdd8,
+ opAndType{OADD, TUINT8}: ssa.OpAdd8,
+ opAndType{OADD, TINT16}: ssa.OpAdd16,
+ opAndType{OADD, TUINT16}: ssa.OpAdd16,
+ opAndType{OADD, TINT32}: ssa.OpAdd32,
+ opAndType{OADD, TUINT32}: ssa.OpAdd32,
+ opAndType{OADD, TPTR32}: ssa.OpAdd32,
+ opAndType{OADD, TINT64}: ssa.OpAdd64,
+ opAndType{OADD, TUINT64}: ssa.OpAdd64,
+ opAndType{OADD, TPTR64}: ssa.OpAdd64,
+ opAndType{OADD, TFLOAT32}: ssa.OpAdd32F,
+ opAndType{OADD, TFLOAT64}: ssa.OpAdd64F,
+
+ opAndType{OSUB, TINT8}: ssa.OpSub8,
+ opAndType{OSUB, TUINT8}: ssa.OpSub8,
+ opAndType{OSUB, TINT16}: ssa.OpSub16,
+ opAndType{OSUB, TUINT16}: ssa.OpSub16,
+ opAndType{OSUB, TINT32}: ssa.OpSub32,
+ opAndType{OSUB, TUINT32}: ssa.OpSub32,
+ opAndType{OSUB, TINT64}: ssa.OpSub64,
+ opAndType{OSUB, TUINT64}: ssa.OpSub64,
+ opAndType{OSUB, TFLOAT32}: ssa.OpSub32F,
+ opAndType{OSUB, TFLOAT64}: ssa.OpSub64F,
+
+ opAndType{ONOT, TBOOL}: ssa.OpNot,
+
+ opAndType{OMINUS, TINT8}: ssa.OpNeg8,
+ opAndType{OMINUS, TUINT8}: ssa.OpNeg8,
+ opAndType{OMINUS, TINT16}: ssa.OpNeg16,
+ opAndType{OMINUS, TUINT16}: ssa.OpNeg16,
+ opAndType{OMINUS, TINT32}: ssa.OpNeg32,
+ opAndType{OMINUS, TUINT32}: ssa.OpNeg32,
+ opAndType{OMINUS, TINT64}: ssa.OpNeg64,
+ opAndType{OMINUS, TUINT64}: ssa.OpNeg64,
+ opAndType{OMINUS, TFLOAT32}: ssa.OpNeg32F,
+ opAndType{OMINUS, TFLOAT64}: ssa.OpNeg64F,
+
+ opAndType{OCOM, TINT8}: ssa.OpCom8,
+ opAndType{OCOM, TUINT8}: ssa.OpCom8,
+ opAndType{OCOM, TINT16}: ssa.OpCom16,
+ opAndType{OCOM, TUINT16}: ssa.OpCom16,
+ opAndType{OCOM, TINT32}: ssa.OpCom32,
+ opAndType{OCOM, TUINT32}: ssa.OpCom32,
+ opAndType{OCOM, TINT64}: ssa.OpCom64,
+ opAndType{OCOM, TUINT64}: ssa.OpCom64,
+
+ opAndType{OIMAG, TCOMPLEX64}: ssa.OpComplexImag,
+ opAndType{OIMAG, TCOMPLEX128}: ssa.OpComplexImag,
+ opAndType{OREAL, TCOMPLEX64}: ssa.OpComplexReal,
+ opAndType{OREAL, TCOMPLEX128}: ssa.OpComplexReal,
+
+ opAndType{OMUL, TINT8}: ssa.OpMul8,
+ opAndType{OMUL, TUINT8}: ssa.OpMul8,
+ opAndType{OMUL, TINT16}: ssa.OpMul16,
+ opAndType{OMUL, TUINT16}: ssa.OpMul16,
+ opAndType{OMUL, TINT32}: ssa.OpMul32,
+ opAndType{OMUL, TUINT32}: ssa.OpMul32,
+ opAndType{OMUL, TINT64}: ssa.OpMul64,
+ opAndType{OMUL, TUINT64}: ssa.OpMul64,
+ opAndType{OMUL, TFLOAT32}: ssa.OpMul32F,
+ opAndType{OMUL, TFLOAT64}: ssa.OpMul64F,
+
+ opAndType{ODIV, TFLOAT32}: ssa.OpDiv32F,
+ opAndType{ODIV, TFLOAT64}: ssa.OpDiv64F,
+
+ opAndType{OHMUL, TINT8}: ssa.OpHmul8,
+ opAndType{OHMUL, TUINT8}: ssa.OpHmul8u,
+ opAndType{OHMUL, TINT16}: ssa.OpHmul16,
+ opAndType{OHMUL, TUINT16}: ssa.OpHmul16u,
+ opAndType{OHMUL, TINT32}: ssa.OpHmul32,
+ opAndType{OHMUL, TUINT32}: ssa.OpHmul32u,
+
+ opAndType{ODIV, TINT8}: ssa.OpDiv8,
+ opAndType{ODIV, TUINT8}: ssa.OpDiv8u,
+ opAndType{ODIV, TINT16}: ssa.OpDiv16,
+ opAndType{ODIV, TUINT16}: ssa.OpDiv16u,
+ opAndType{ODIV, TINT32}: ssa.OpDiv32,
+ opAndType{ODIV, TUINT32}: ssa.OpDiv32u,
+ opAndType{ODIV, TINT64}: ssa.OpDiv64,
+ opAndType{ODIV, TUINT64}: ssa.OpDiv64u,
+
+ opAndType{OMOD, TINT8}: ssa.OpMod8,
+ opAndType{OMOD, TUINT8}: ssa.OpMod8u,
+ opAndType{OMOD, TINT16}: ssa.OpMod16,
+ opAndType{OMOD, TUINT16}: ssa.OpMod16u,
+ opAndType{OMOD, TINT32}: ssa.OpMod32,
+ opAndType{OMOD, TUINT32}: ssa.OpMod32u,
+ opAndType{OMOD, TINT64}: ssa.OpMod64,
+ opAndType{OMOD, TUINT64}: ssa.OpMod64u,
+
+ opAndType{OAND, TINT8}: ssa.OpAnd8,
+ opAndType{OAND, TUINT8}: ssa.OpAnd8,
+ opAndType{OAND, TINT16}: ssa.OpAnd16,
+ opAndType{OAND, TUINT16}: ssa.OpAnd16,
+ opAndType{OAND, TINT32}: ssa.OpAnd32,
+ opAndType{OAND, TUINT32}: ssa.OpAnd32,
+ opAndType{OAND, TINT64}: ssa.OpAnd64,
+ opAndType{OAND, TUINT64}: ssa.OpAnd64,
+
+ opAndType{OOR, TINT8}: ssa.OpOr8,
+ opAndType{OOR, TUINT8}: ssa.OpOr8,
+ opAndType{OOR, TINT16}: ssa.OpOr16,
+ opAndType{OOR, TUINT16}: ssa.OpOr16,
+ opAndType{OOR, TINT32}: ssa.OpOr32,
+ opAndType{OOR, TUINT32}: ssa.OpOr32,
+ opAndType{OOR, TINT64}: ssa.OpOr64,
+ opAndType{OOR, TUINT64}: ssa.OpOr64,
+
+ opAndType{OXOR, TINT8}: ssa.OpXor8,
+ opAndType{OXOR, TUINT8}: ssa.OpXor8,
+ opAndType{OXOR, TINT16}: ssa.OpXor16,
+ opAndType{OXOR, TUINT16}: ssa.OpXor16,
+ opAndType{OXOR, TINT32}: ssa.OpXor32,
+ opAndType{OXOR, TUINT32}: ssa.OpXor32,
+ opAndType{OXOR, TINT64}: ssa.OpXor64,
+ opAndType{OXOR, TUINT64}: ssa.OpXor64,
+
+ opAndType{OEQ, TBOOL}: ssa.OpEq8,
+ opAndType{OEQ, TINT8}: ssa.OpEq8,
+ opAndType{OEQ, TUINT8}: ssa.OpEq8,
+ opAndType{OEQ, TINT16}: ssa.OpEq16,
+ opAndType{OEQ, TUINT16}: ssa.OpEq16,
+ opAndType{OEQ, TINT32}: ssa.OpEq32,
+ opAndType{OEQ, TUINT32}: ssa.OpEq32,
+ opAndType{OEQ, TINT64}: ssa.OpEq64,
+ opAndType{OEQ, TUINT64}: ssa.OpEq64,
+ opAndType{OEQ, TINTER}: ssa.OpEqFat, // e == nil only
+ opAndType{OEQ, TARRAY}: ssa.OpEqFat, // slice only; a == nil only
+ opAndType{OEQ, TFUNC}: ssa.OpEqPtr,
+ opAndType{OEQ, TMAP}: ssa.OpEqPtr,
+ opAndType{OEQ, TCHAN}: ssa.OpEqPtr,
+ opAndType{OEQ, TPTR64}: ssa.OpEqPtr,
+ opAndType{OEQ, TUINTPTR}: ssa.OpEqPtr,
+ opAndType{OEQ, TUNSAFEPTR}: ssa.OpEqPtr,
+ opAndType{OEQ, TFLOAT64}: ssa.OpEq64F,
+ opAndType{OEQ, TFLOAT32}: ssa.OpEq32F,
+
+ opAndType{ONE, TBOOL}: ssa.OpNeq8,
+ opAndType{ONE, TINT8}: ssa.OpNeq8,
+ opAndType{ONE, TUINT8}: ssa.OpNeq8,
+ opAndType{ONE, TINT16}: ssa.OpNeq16,
+ opAndType{ONE, TUINT16}: ssa.OpNeq16,
+ opAndType{ONE, TINT32}: ssa.OpNeq32,
+ opAndType{ONE, TUINT32}: ssa.OpNeq32,
+ opAndType{ONE, TINT64}: ssa.OpNeq64,
+ opAndType{ONE, TUINT64}: ssa.OpNeq64,
+ opAndType{ONE, TINTER}: ssa.OpNeqFat, // e != nil only
+ opAndType{ONE, TARRAY}: ssa.OpNeqFat, // slice only; a != nil only
+ opAndType{ONE, TFUNC}: ssa.OpNeqPtr,
+ opAndType{ONE, TMAP}: ssa.OpNeqPtr,
+ opAndType{ONE, TCHAN}: ssa.OpNeqPtr,
+ opAndType{ONE, TPTR64}: ssa.OpNeqPtr,
+ opAndType{ONE, TUINTPTR}: ssa.OpNeqPtr,
+ opAndType{ONE, TUNSAFEPTR}: ssa.OpNeqPtr,
+ opAndType{ONE, TFLOAT64}: ssa.OpNeq64F,
+ opAndType{ONE, TFLOAT32}: ssa.OpNeq32F,
+
+ opAndType{OLT, TINT8}: ssa.OpLess8,
+ opAndType{OLT, TUINT8}: ssa.OpLess8U,
+ opAndType{OLT, TINT16}: ssa.OpLess16,
+ opAndType{OLT, TUINT16}: ssa.OpLess16U,
+ opAndType{OLT, TINT32}: ssa.OpLess32,
+ opAndType{OLT, TUINT32}: ssa.OpLess32U,
+ opAndType{OLT, TINT64}: ssa.OpLess64,
+ opAndType{OLT, TUINT64}: ssa.OpLess64U,
+ opAndType{OLT, TFLOAT64}: ssa.OpLess64F,
+ opAndType{OLT, TFLOAT32}: ssa.OpLess32F,
+
+ opAndType{OGT, TINT8}: ssa.OpGreater8,
+ opAndType{OGT, TUINT8}: ssa.OpGreater8U,
+ opAndType{OGT, TINT16}: ssa.OpGreater16,
+ opAndType{OGT, TUINT16}: ssa.OpGreater16U,
+ opAndType{OGT, TINT32}: ssa.OpGreater32,
+ opAndType{OGT, TUINT32}: ssa.OpGreater32U,
+ opAndType{OGT, TINT64}: ssa.OpGreater64,
+ opAndType{OGT, TUINT64}: ssa.OpGreater64U,
+ opAndType{OGT, TFLOAT64}: ssa.OpGreater64F,
+ opAndType{OGT, TFLOAT32}: ssa.OpGreater32F,
+
+ opAndType{OLE, TINT8}: ssa.OpLeq8,
+ opAndType{OLE, TUINT8}: ssa.OpLeq8U,
+ opAndType{OLE, TINT16}: ssa.OpLeq16,
+ opAndType{OLE, TUINT16}: ssa.OpLeq16U,
+ opAndType{OLE, TINT32}: ssa.OpLeq32,
+ opAndType{OLE, TUINT32}: ssa.OpLeq32U,
+ opAndType{OLE, TINT64}: ssa.OpLeq64,
+ opAndType{OLE, TUINT64}: ssa.OpLeq64U,
+ opAndType{OLE, TFLOAT64}: ssa.OpLeq64F,
+ opAndType{OLE, TFLOAT32}: ssa.OpLeq32F,
+
+ opAndType{OGE, TINT8}: ssa.OpGeq8,
+ opAndType{OGE, TUINT8}: ssa.OpGeq8U,
+ opAndType{OGE, TINT16}: ssa.OpGeq16,
+ opAndType{OGE, TUINT16}: ssa.OpGeq16U,
+ opAndType{OGE, TINT32}: ssa.OpGeq32,
+ opAndType{OGE, TUINT32}: ssa.OpGeq32U,
+ opAndType{OGE, TINT64}: ssa.OpGeq64,
+ opAndType{OGE, TUINT64}: ssa.OpGeq64U,
+ opAndType{OGE, TFLOAT64}: ssa.OpGeq64F,
+ opAndType{OGE, TFLOAT32}: ssa.OpGeq32F,
+
+ opAndType{OLROT, TUINT8}: ssa.OpLrot8,
+ opAndType{OLROT, TUINT16}: ssa.OpLrot16,
+ opAndType{OLROT, TUINT32}: ssa.OpLrot32,
+ opAndType{OLROT, TUINT64}: ssa.OpLrot64,
+}
+
+func (s *state) concreteEtype(t *Type) uint8 {
+ e := t.Etype
+ switch e {
+ default:
+ return e
+ case TINT:
+ if s.config.IntSize == 8 {
+ return TINT64
+ }
+ return TINT32
+ case TUINT:
+ if s.config.IntSize == 8 {
+ return TUINT64
+ }
+ return TUINT32
+ case TUINTPTR:
+ if s.config.PtrSize == 8 {
+ return TUINT64
+ }
+ return TUINT32
+ }
+}
+
+func (s *state) ssaOp(op uint8, t *Type) ssa.Op {
+ etype := s.concreteEtype(t)
+ x, ok := opToSSA[opAndType{op, etype}]
+ if !ok {
+ s.Unimplementedf("unhandled binary op %s %s", opnames[op], Econv(int(etype), 0))
+ }
+ return x
+}
+
+func floatForComplex(t *Type) *Type {
+ if t.Size() == 8 {
+ return Types[TFLOAT32]
+ } else {
+ return Types[TFLOAT64]
+ }
+}
+
+type opAndTwoTypes struct {
+ op uint8
+ etype1 uint8
+ etype2 uint8
+}
+
+type twoTypes struct {
+ etype1 uint8
+ etype2 uint8
+}
+
+type twoOpsAndType struct {
+ op1 ssa.Op
+ op2 ssa.Op
+ intermediateType uint8
+}
+
+var fpConvOpToSSA = map[twoTypes]twoOpsAndType{
+
+ twoTypes{TINT8, TFLOAT32}: twoOpsAndType{ssa.OpSignExt8to32, ssa.OpCvt32to32F, TINT32},
+ twoTypes{TINT16, TFLOAT32}: twoOpsAndType{ssa.OpSignExt16to32, ssa.OpCvt32to32F, TINT32},
+ twoTypes{TINT32, TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32to32F, TINT32},
+ twoTypes{TINT64, TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64to32F, TINT64},
+
+ twoTypes{TINT8, TFLOAT64}: twoOpsAndType{ssa.OpSignExt8to32, ssa.OpCvt32to64F, TINT32},
+ twoTypes{TINT16, TFLOAT64}: twoOpsAndType{ssa.OpSignExt16to32, ssa.OpCvt32to64F, TINT32},
+ twoTypes{TINT32, TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32to64F, TINT32},
+ twoTypes{TINT64, TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64to64F, TINT64},
+
+ twoTypes{TFLOAT32, TINT8}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to8, TINT32},
+ twoTypes{TFLOAT32, TINT16}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to16, TINT32},
+ twoTypes{TFLOAT32, TINT32}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpCopy, TINT32},
+ twoTypes{TFLOAT32, TINT64}: twoOpsAndType{ssa.OpCvt32Fto64, ssa.OpCopy, TINT64},
+
+ twoTypes{TFLOAT64, TINT8}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to8, TINT32},
+ twoTypes{TFLOAT64, TINT16}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to16, TINT32},
+ twoTypes{TFLOAT64, TINT32}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpCopy, TINT32},
+ twoTypes{TFLOAT64, TINT64}: twoOpsAndType{ssa.OpCvt64Fto64, ssa.OpCopy, TINT64},
+ // unsigned
+ twoTypes{TUINT8, TFLOAT32}: twoOpsAndType{ssa.OpZeroExt8to32, ssa.OpCvt32to32F, TINT32},
+ twoTypes{TUINT16, TFLOAT32}: twoOpsAndType{ssa.OpZeroExt16to32, ssa.OpCvt32to32F, TINT32},
+ twoTypes{TUINT32, TFLOAT32}: twoOpsAndType{ssa.OpZeroExt32to64, ssa.OpCvt64to32F, TINT64}, // go wide to dodge unsigned
+ twoTypes{TUINT64, TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpInvalid, TUINT64}, // Cvt64Uto32F, branchy code expansion instead
+
+ twoTypes{TUINT8, TFLOAT64}: twoOpsAndType{ssa.OpZeroExt8to32, ssa.OpCvt32to64F, TINT32},
+ twoTypes{TUINT16, TFLOAT64}: twoOpsAndType{ssa.OpZeroExt16to32, ssa.OpCvt32to64F, TINT32},
+ twoTypes{TUINT32, TFLOAT64}: twoOpsAndType{ssa.OpZeroExt32to64, ssa.OpCvt64to64F, TINT64}, // go wide to dodge unsigned
+ twoTypes{TUINT64, TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpInvalid, TUINT64}, // Cvt64Uto64F, branchy code expansion instead
+
+ twoTypes{TFLOAT32, TUINT8}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to8, TINT32},
+ twoTypes{TFLOAT32, TUINT16}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to16, TINT32},
+ twoTypes{TFLOAT32, TUINT32}: twoOpsAndType{ssa.OpCvt32Fto64, ssa.OpTrunc64to32, TINT64}, // go wide to dodge unsigned
+ twoTypes{TFLOAT32, TUINT64}: twoOpsAndType{ssa.OpInvalid, ssa.OpCopy, TUINT64}, // Cvt32Fto64U, branchy code expansion instead
+
+ twoTypes{TFLOAT64, TUINT8}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to8, TINT32},
+ twoTypes{TFLOAT64, TUINT16}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to16, TINT32},
+ twoTypes{TFLOAT64, TUINT32}: twoOpsAndType{ssa.OpCvt64Fto64, ssa.OpTrunc64to32, TINT64}, // go wide to dodge unsigned
+ twoTypes{TFLOAT64, TUINT64}: twoOpsAndType{ssa.OpInvalid, ssa.OpCopy, TUINT64}, // Cvt64Fto64U, branchy code expansion instead
+
+ // float
+ twoTypes{TFLOAT64, TFLOAT32}: twoOpsAndType{ssa.OpCvt64Fto32F, ssa.OpCopy, TFLOAT32},
+ twoTypes{TFLOAT64, TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCopy, TFLOAT64},
+ twoTypes{TFLOAT32, TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCopy, TFLOAT32},
+ twoTypes{TFLOAT32, TFLOAT64}: twoOpsAndType{ssa.OpCvt32Fto64F, ssa.OpCopy, TFLOAT64},
+}
+
+var shiftOpToSSA = map[opAndTwoTypes]ssa.Op{
+ opAndTwoTypes{OLSH, TINT8, TUINT8}: ssa.OpLsh8x8,
+ opAndTwoTypes{OLSH, TUINT8, TUINT8}: ssa.OpLsh8x8,
+ opAndTwoTypes{OLSH, TINT8, TUINT16}: ssa.OpLsh8x16,
+ opAndTwoTypes{OLSH, TUINT8, TUINT16}: ssa.OpLsh8x16,
+ opAndTwoTypes{OLSH, TINT8, TUINT32}: ssa.OpLsh8x32,
+ opAndTwoTypes{OLSH, TUINT8, TUINT32}: ssa.OpLsh8x32,
+ opAndTwoTypes{OLSH, TINT8, TUINT64}: ssa.OpLsh8x64,
+ opAndTwoTypes{OLSH, TUINT8, TUINT64}: ssa.OpLsh8x64,
+
+ opAndTwoTypes{OLSH, TINT16, TUINT8}: ssa.OpLsh16x8,
+ opAndTwoTypes{OLSH, TUINT16, TUINT8}: ssa.OpLsh16x8,
+ opAndTwoTypes{OLSH, TINT16, TUINT16}: ssa.OpLsh16x16,
+ opAndTwoTypes{OLSH, TUINT16, TUINT16}: ssa.OpLsh16x16,
+ opAndTwoTypes{OLSH, TINT16, TUINT32}: ssa.OpLsh16x32,
+ opAndTwoTypes{OLSH, TUINT16, TUINT32}: ssa.OpLsh16x32,
+ opAndTwoTypes{OLSH, TINT16, TUINT64}: ssa.OpLsh16x64,
+ opAndTwoTypes{OLSH, TUINT16, TUINT64}: ssa.OpLsh16x64,
+
+ opAndTwoTypes{OLSH, TINT32, TUINT8}: ssa.OpLsh32x8,
+ opAndTwoTypes{OLSH, TUINT32, TUINT8}: ssa.OpLsh32x8,
+ opAndTwoTypes{OLSH, TINT32, TUINT16}: ssa.OpLsh32x16,
+ opAndTwoTypes{OLSH, TUINT32, TUINT16}: ssa.OpLsh32x16,
+ opAndTwoTypes{OLSH, TINT32, TUINT32}: ssa.OpLsh32x32,
+ opAndTwoTypes{OLSH, TUINT32, TUINT32}: ssa.OpLsh32x32,
+ opAndTwoTypes{OLSH, TINT32, TUINT64}: ssa.OpLsh32x64,
+ opAndTwoTypes{OLSH, TUINT32, TUINT64}: ssa.OpLsh32x64,
+
+ opAndTwoTypes{OLSH, TINT64, TUINT8}: ssa.OpLsh64x8,
+ opAndTwoTypes{OLSH, TUINT64, TUINT8}: ssa.OpLsh64x8,
+ opAndTwoTypes{OLSH, TINT64, TUINT16}: ssa.OpLsh64x16,
+ opAndTwoTypes{OLSH, TUINT64, TUINT16}: ssa.OpLsh64x16,
+ opAndTwoTypes{OLSH, TINT64, TUINT32}: ssa.OpLsh64x32,
+ opAndTwoTypes{OLSH, TUINT64, TUINT32}: ssa.OpLsh64x32,
+ opAndTwoTypes{OLSH, TINT64, TUINT64}: ssa.OpLsh64x64,
+ opAndTwoTypes{OLSH, TUINT64, TUINT64}: ssa.OpLsh64x64,
+
+ opAndTwoTypes{ORSH, TINT8, TUINT8}: ssa.OpRsh8x8,
+ opAndTwoTypes{ORSH, TUINT8, TUINT8}: ssa.OpRsh8Ux8,
+ opAndTwoTypes{ORSH, TINT8, TUINT16}: ssa.OpRsh8x16,
+ opAndTwoTypes{ORSH, TUINT8, TUINT16}: ssa.OpRsh8Ux16,
+ opAndTwoTypes{ORSH, TINT8, TUINT32}: ssa.OpRsh8x32,
+ opAndTwoTypes{ORSH, TUINT8, TUINT32}: ssa.OpRsh8Ux32,
+ opAndTwoTypes{ORSH, TINT8, TUINT64}: ssa.OpRsh8x64,
+ opAndTwoTypes{ORSH, TUINT8, TUINT64}: ssa.OpRsh8Ux64,
+
+ opAndTwoTypes{ORSH, TINT16, TUINT8}: ssa.OpRsh16x8,
+ opAndTwoTypes{ORSH, TUINT16, TUINT8}: ssa.OpRsh16Ux8,
+ opAndTwoTypes{ORSH, TINT16, TUINT16}: ssa.OpRsh16x16,
+ opAndTwoTypes{ORSH, TUINT16, TUINT16}: ssa.OpRsh16Ux16,
+ opAndTwoTypes{ORSH, TINT16, TUINT32}: ssa.OpRsh16x32,
+ opAndTwoTypes{ORSH, TUINT16, TUINT32}: ssa.OpRsh16Ux32,
+ opAndTwoTypes{ORSH, TINT16, TUINT64}: ssa.OpRsh16x64,
+ opAndTwoTypes{ORSH, TUINT16, TUINT64}: ssa.OpRsh16Ux64,
+
+ opAndTwoTypes{ORSH, TINT32, TUINT8}: ssa.OpRsh32x8,
+ opAndTwoTypes{ORSH, TUINT32, TUINT8}: ssa.OpRsh32Ux8,
+ opAndTwoTypes{ORSH, TINT32, TUINT16}: ssa.OpRsh32x16,
+ opAndTwoTypes{ORSH, TUINT32, TUINT16}: ssa.OpRsh32Ux16,
+ opAndTwoTypes{ORSH, TINT32, TUINT32}: ssa.OpRsh32x32,
+ opAndTwoTypes{ORSH, TUINT32, TUINT32}: ssa.OpRsh32Ux32,
+ opAndTwoTypes{ORSH, TINT32, TUINT64}: ssa.OpRsh32x64,
+ opAndTwoTypes{ORSH, TUINT32, TUINT64}: ssa.OpRsh32Ux64,
+
+ opAndTwoTypes{ORSH, TINT64, TUINT8}: ssa.OpRsh64x8,
+ opAndTwoTypes{ORSH, TUINT64, TUINT8}: ssa.OpRsh64Ux8,
+ opAndTwoTypes{ORSH, TINT64, TUINT16}: ssa.OpRsh64x16,
+ opAndTwoTypes{ORSH, TUINT64, TUINT16}: ssa.OpRsh64Ux16,
+ opAndTwoTypes{ORSH, TINT64, TUINT32}: ssa.OpRsh64x32,
+ opAndTwoTypes{ORSH, TUINT64, TUINT32}: ssa.OpRsh64Ux32,
+ opAndTwoTypes{ORSH, TINT64, TUINT64}: ssa.OpRsh64x64,
+ opAndTwoTypes{ORSH, TUINT64, TUINT64}: ssa.OpRsh64Ux64,
+}
+
+func (s *state) ssaShiftOp(op uint8, t *Type, u *Type) ssa.Op {
+ etype1 := s.concreteEtype(t)
+ etype2 := s.concreteEtype(u)
+ x, ok := shiftOpToSSA[opAndTwoTypes{op, etype1, etype2}]
+ if !ok {
+ s.Unimplementedf("unhandled shift op %s etype=%s/%s", opnames[op], Econv(int(etype1), 0), Econv(int(etype2), 0))
+ }
+ return x
+}
+
+func (s *state) ssaRotateOp(op uint8, t *Type) ssa.Op {
+ etype1 := s.concreteEtype(t)
+ x, ok := opToSSA[opAndType{op, etype1}]
+ if !ok {
+ s.Unimplementedf("unhandled rotate op %s etype=%s", opnames[op], Econv(int(etype1), 0))
+ }
+ return x
+}
+
+// expr converts the expression n to ssa, adds it to s and returns the ssa result.
+func (s *state) expr(n *Node) *ssa.Value {
+ s.pushLine(n.Lineno)
+ defer s.popLine()
+
+ s.stmtList(n.Ninit)
+ switch n.Op {
+ case ONAME:
+ if n.Class == PFUNC {
+ // "value" of a function is the address of the function's closure
+ sym := funcsym(n.Sym)
+ aux := &ssa.ExternSymbol{n.Type, sym}
+ return s.entryNewValue1A(ssa.OpAddr, Ptrto(n.Type), aux, s.sb)
+ }
+ if canSSA(n) {
+ return s.variable(n, n.Type)
+ }
+ addr := s.addr(n)
+ return s.newValue2(ssa.OpLoad, n.Type, addr, s.mem())
+ case OLITERAL:
+ switch n.Val().Ctype() {
+ case CTINT:
+ i := Mpgetfix(n.Val().U.(*Mpint))
+ switch n.Type.Size() {
+ case 1:
+ return s.constInt8(n.Type, int8(i))
+ case 2:
+ return s.constInt16(n.Type, int16(i))
+ case 4:
+ return s.constInt32(n.Type, int32(i))
+ case 8:
+ return s.constInt64(n.Type, i)
+ default:
+ s.Fatalf("bad integer size %d", n.Type.Size())
+ return nil
+ }
+ case CTSTR:
+ return s.entryNewValue0A(ssa.OpConstString, n.Type, n.Val().U)
+ case CTBOOL:
+ if n.Val().U.(bool) {
+ return s.entryNewValue0I(ssa.OpConstBool, Types[TBOOL], 1) // 1 = true
+ } else {
+ return s.entryNewValue0I(ssa.OpConstBool, Types[TBOOL], 0) // 0 = false
+ }
+ case CTNIL:
+ t := n.Type
+ switch {
+ case t.IsSlice():
+ return s.entryNewValue0(ssa.OpConstSlice, t)
+ case t.IsInterface():
+ return s.entryNewValue0(ssa.OpConstInterface, t)
+ default:
+ return s.entryNewValue0(ssa.OpConstNil, t)
+ }
+ case CTFLT:
+ f := n.Val().U.(*Mpflt)
+ switch n.Type.Size() {
+ case 4:
+ return s.constFloat32(n.Type, mpgetflt32(f))
+ case 8:
+ return s.constFloat64(n.Type, mpgetflt(f))
+ default:
+ s.Fatalf("bad float size %d", n.Type.Size())
+ return nil
+ }
+ case CTCPLX:
+ c := n.Val().U.(*Mpcplx)
+ r := &c.Real
+ i := &c.Imag
+ switch n.Type.Size() {
+ case 8:
+ {
+ pt := Types[TFLOAT32]
+ return s.newValue2(ssa.OpComplexMake, n.Type,
+ s.constFloat32(pt, mpgetflt32(r)),
+ s.constFloat32(pt, mpgetflt32(i)))
+ }
+ case 16:
+ {
+ pt := Types[TFLOAT64]
+ return s.newValue2(ssa.OpComplexMake, n.Type,
+ s.constFloat64(pt, mpgetflt(r)),
+ s.constFloat64(pt, mpgetflt(i)))
+ }
+ default:
+ s.Fatalf("bad float size %d", n.Type.Size())
+ return nil
+ }
+
+ default:
+ s.Unimplementedf("unhandled OLITERAL %v", n.Val().Ctype())
+ return nil
+ }
+ case OCONVNOP:
+ to := n.Type
+ from := n.Left.Type
+ if to.Etype == TFUNC {
+ s.Unimplementedf("CONVNOP closure")
+ return nil
+ }
+
+ // Assume everything will work out, so set up our return value.
+ // Anything interesting that happens from here is a fatal.
+ x := s.expr(n.Left)
+ v := s.newValue1(ssa.OpCopy, to, x) // ensure that v has the right type
+
+ // named <--> unnamed type or typed <--> untyped const
+ if from.Etype == to.Etype {
+ return v
+ }
+ // unsafe.Pointer <--> *T
+ if to.Etype == TUNSAFEPTR && from.IsPtr() || from.Etype == TUNSAFEPTR && to.IsPtr() {
+ return v
+ }
+
+ dowidth(from)
+ dowidth(to)
+ if from.Width != to.Width {
+ s.Fatalf("CONVNOP width mismatch %v (%d) -> %v (%d)\n", from, from.Width, to, to.Width)
+ return nil
+ }
+ if etypesign(from.Etype) != etypesign(to.Etype) {
+ s.Fatalf("CONVNOP sign mismatch %v (%s) -> %v (%s)\n", from, Econv(int(from.Etype), 0), to, Econv(int(to.Etype), 0))
+ return nil
+ }
+
+ if flag_race != 0 {
+ s.Unimplementedf("questionable CONVNOP from race detector %v -> %v\n", from, to)
+ return nil
+ }
+
+ if etypesign(from.Etype) == 0 {
+ s.Fatalf("CONVNOP unrecognized non-integer %v -> %v\n", from, to)
+ return nil
+ }
+
+ // integer, same width, same sign
+ return v
+
+ case OCONV:
+ x := s.expr(n.Left)
+ ft := n.Left.Type // from type
+ tt := n.Type // to type
+ if ft.IsInteger() && tt.IsInteger() {
+ var op ssa.Op
+ if tt.Size() == ft.Size() {
+ op = ssa.OpCopy
+ } else if tt.Size() < ft.Size() {
+ // truncation
+ switch 10*ft.Size() + tt.Size() {
+ case 21:
+ op = ssa.OpTrunc16to8
+ case 41:
+ op = ssa.OpTrunc32to8
+ case 42:
+ op = ssa.OpTrunc32to16
+ case 81:
+ op = ssa.OpTrunc64to8
+ case 82:
+ op = ssa.OpTrunc64to16
+ case 84:
+ op = ssa.OpTrunc64to32
+ default:
+ s.Fatalf("weird integer truncation %s -> %s", ft, tt)
+ }
+ } else if ft.IsSigned() {
+ // sign extension
+ switch 10*ft.Size() + tt.Size() {
+ case 12:
+ op = ssa.OpSignExt8to16
+ case 14:
+ op = ssa.OpSignExt8to32
+ case 18:
+ op = ssa.OpSignExt8to64
+ case 24:
+ op = ssa.OpSignExt16to32
+ case 28:
+ op = ssa.OpSignExt16to64
+ case 48:
+ op = ssa.OpSignExt32to64
+ default:
+ s.Fatalf("bad integer sign extension %s -> %s", ft, tt)
+ }
+ } else {
+ // zero extension
+ switch 10*ft.Size() + tt.Size() {
+ case 12:
+ op = ssa.OpZeroExt8to16
+ case 14:
+ op = ssa.OpZeroExt8to32
+ case 18:
+ op = ssa.OpZeroExt8to64
+ case 24:
+ op = ssa.OpZeroExt16to32
+ case 28:
+ op = ssa.OpZeroExt16to64
+ case 48:
+ op = ssa.OpZeroExt32to64
+ default:
+ s.Fatalf("weird integer sign extension %s -> %s", ft, tt)
+ }
+ }
+ return s.newValue1(op, n.Type, x)
+ }
+
+ if ft.IsFloat() || tt.IsFloat() {
+ conv, ok := fpConvOpToSSA[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]
+ if !ok {
+ s.Fatalf("weird float conversion %s -> %s", ft, tt)
+ }
+ op1, op2, it := conv.op1, conv.op2, conv.intermediateType
+
+ if op1 != ssa.OpInvalid && op2 != ssa.OpInvalid {
+ // normal case, not tripping over unsigned 64
+ if op1 == ssa.OpCopy {
+ if op2 == ssa.OpCopy {
+ return x
+ }
+ return s.newValue1(op2, n.Type, x)
+ }
+ if op2 == ssa.OpCopy {
+ return s.newValue1(op1, n.Type, x)
+ }
+ return s.newValue1(op2, n.Type, s.newValue1(op1, Types[it], x))
+ }
+ // Tricky 64-bit unsigned cases.
+ if ft.IsInteger() {
+ // therefore tt is float32 or float64, and ft is also unsigned
+ if tt.Size() == 4 {
+ return s.uint64Tofloat32(n, x, ft, tt)
+ }
+ if tt.Size() == 8 {
+ return s.uint64Tofloat64(n, x, ft, tt)
+ }
+ s.Fatalf("weird unsigned integer to float conversion %s -> %s", ft, tt)
+ }
+ // therefore ft is float32 or float64, and tt is unsigned integer
+ if ft.Size() == 4 {
+ return s.float32ToUint64(n, x, ft, tt)
+ }
+ if ft.Size() == 8 {
+ return s.float64ToUint64(n, x, ft, tt)
+ }
+ s.Fatalf("weird float to unsigned integer conversion %s -> %s", ft, tt)
+ return nil
+ }
+
+ if ft.IsComplex() && tt.IsComplex() {
+ var op ssa.Op
+ if ft.Size() == tt.Size() {
+ op = ssa.OpCopy
+ } else if ft.Size() == 8 && tt.Size() == 16 {
+ op = ssa.OpCvt32Fto64F
+ } else if ft.Size() == 16 && tt.Size() == 8 {
+ op = ssa.OpCvt64Fto32F
+ } else {
+ s.Fatalf("weird complex conversion %s -> %s", ft, tt)
+ }
+ ftp := floatForComplex(ft)
+ ttp := floatForComplex(tt)
+ return s.newValue2(ssa.OpComplexMake, tt,
+ s.newValue1(op, ttp, s.newValue1(ssa.OpComplexReal, ftp, x)),
+ s.newValue1(op, ttp, s.newValue1(ssa.OpComplexImag, ftp, x)))
+ }
+
+ s.Unimplementedf("unhandled OCONV %s -> %s", Econv(int(n.Left.Type.Etype), 0), Econv(int(n.Type.Etype), 0))
+ return nil
+
+ // binary ops
+ case OLT, OEQ, ONE, OLE, OGE, OGT:
+ a := s.expr(n.Left)
+ b := s.expr(n.Right)
+ return s.newValue2(s.ssaOp(n.Op, n.Left.Type), Types[TBOOL], a, b)
+ case OMUL:
+ a := s.expr(n.Left)
+ b := s.expr(n.Right)
+ if n.Type.IsComplex() {
+ mulop := ssa.OpMul64F
+ addop := ssa.OpAdd64F
+ subop := ssa.OpSub64F
+ pt := floatForComplex(n.Type) // Could be Float32 or Float64
+ wt := Types[TFLOAT64] // Compute in Float64 to minimize cancellation error
+
+ areal := s.newValue1(ssa.OpComplexReal, pt, a)
+ breal := s.newValue1(ssa.OpComplexReal, pt, b)
+ aimag := s.newValue1(ssa.OpComplexImag, pt, a)
+ bimag := s.newValue1(ssa.OpComplexImag, pt, b)
+
+ if pt != wt { // Widen for calculation
+ areal = s.newValue1(ssa.OpCvt32Fto64F, wt, areal)
+ breal = s.newValue1(ssa.OpCvt32Fto64F, wt, breal)
+ aimag = s.newValue1(ssa.OpCvt32Fto64F, wt, aimag)
+ bimag = s.newValue1(ssa.OpCvt32Fto64F, wt, bimag)
+ }
+
+ xreal := s.newValue2(subop, wt, s.newValue2(mulop, wt, areal, breal), s.newValue2(mulop, wt, aimag, bimag))
+ ximag := s.newValue2(addop, wt, s.newValue2(mulop, wt, areal, bimag), s.newValue2(mulop, wt, aimag, breal))
+
+ if pt != wt { // Narrow to store back
+ xreal = s.newValue1(ssa.OpCvt64Fto32F, pt, xreal)
+ ximag = s.newValue1(ssa.OpCvt64Fto32F, pt, ximag)
+ }
+
+ return s.newValue2(ssa.OpComplexMake, n.Type, xreal, ximag)
+ }
+ return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
+
+ case ODIV:
+ a := s.expr(n.Left)
+ b := s.expr(n.Right)
+ if n.Type.IsComplex() {
+ // TODO this is not executed because the front-end substitutes a runtime call.
+ // That probably ought to change; with modest optimization the widen/narrow
+ // conversions could all be elided in larger expression trees.
+ mulop := ssa.OpMul64F
+ addop := ssa.OpAdd64F
+ subop := ssa.OpSub64F
+ divop := ssa.OpDiv64F
+ pt := floatForComplex(n.Type) // Could be Float32 or Float64
+ wt := Types[TFLOAT64] // Compute in Float64 to minimize cancellation error
+
+ areal := s.newValue1(ssa.OpComplexReal, pt, a)
+ breal := s.newValue1(ssa.OpComplexReal, pt, b)
+ aimag := s.newValue1(ssa.OpComplexImag, pt, a)
+ bimag := s.newValue1(ssa.OpComplexImag, pt, b)
+
+ if pt != wt { // Widen for calculation
+ areal = s.newValue1(ssa.OpCvt32Fto64F, wt, areal)
+ breal = s.newValue1(ssa.OpCvt32Fto64F, wt, breal)
+ aimag = s.newValue1(ssa.OpCvt32Fto64F, wt, aimag)
+ bimag = s.newValue1(ssa.OpCvt32Fto64F, wt, bimag)
+ }
+
+ denom := s.newValue2(addop, wt, s.newValue2(mulop, wt, breal, breal), s.newValue2(mulop, wt, bimag, bimag))
+ xreal := s.newValue2(addop, wt, s.newValue2(mulop, wt, areal, breal), s.newValue2(mulop, wt, aimag, bimag))
+ ximag := s.newValue2(subop, wt, s.newValue2(mulop, wt, aimag, breal), s.newValue2(mulop, wt, areal, bimag))
+
+ // TODO not sure if this is best done in wide precision or narrow
+ // Double-rounding might be an issue.
+ // Note that the pre-SSA implementation does the entire calculation
+ // in wide format, so wide is compatible.
+ xreal = s.newValue2(divop, wt, xreal, denom)
+ ximag = s.newValue2(divop, wt, ximag, denom)
+
+ if pt != wt { // Narrow to store back
+ xreal = s.newValue1(ssa.OpCvt64Fto32F, pt, xreal)
+ ximag = s.newValue1(ssa.OpCvt64Fto32F, pt, ximag)
+ }
+
+ return s.newValue2(ssa.OpComplexMake, n.Type, xreal, ximag)
+ }
+ return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
+ case OADD, OSUB:
+ a := s.expr(n.Left)
+ b := s.expr(n.Right)
+ if n.Type.IsComplex() {
+ pt := floatForComplex(n.Type)
+ op := s.ssaOp(n.Op, pt)
+ return s.newValue2(ssa.OpComplexMake, n.Type,
+ s.newValue2(op, pt, s.newValue1(ssa.OpComplexReal, pt, a), s.newValue1(ssa.OpComplexReal, pt, b)),
+ s.newValue2(op, pt, s.newValue1(ssa.OpComplexImag, pt, a), s.newValue1(ssa.OpComplexImag, pt, b)))
+ }
+ return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
+ case OAND, OOR, OMOD, OHMUL, OXOR:
+ a := s.expr(n.Left)
+ b := s.expr(n.Right)
+ return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
+ case OLSH, ORSH:
+ a := s.expr(n.Left)
+ b := s.expr(n.Right)
+ return s.newValue2(s.ssaShiftOp(n.Op, n.Type, n.Right.Type), a.Type, a, b)
+ case OLROT:
+ a := s.expr(n.Left)
+ i := n.Right.Int()
+ if i <= 0 || i >= n.Type.Size()*8 {
+ s.Fatalf("Wrong rotate distance for LROT, expected 1 through %d, saw %d", n.Type.Size()*8-1, i)
+ }
+ return s.newValue1I(s.ssaRotateOp(n.Op, n.Type), a.Type, i, a)
+ case OANDAND, OOROR:
+ // To implement OANDAND (and OOROR), we introduce a
+ // new temporary variable to hold the result. The
+ // variable is associated with the OANDAND node in the
+ // s.vars table (normally variables are only
+ // associated with ONAME nodes). We convert
+ // A && B
+ // to
+ // var = A
+ // if var {
+ // var = B
+ // }
+ // Using var in the subsequent block introduces the
+ // necessary phi variable.
+ el := s.expr(n.Left)
+ s.vars[n] = el
+
+ b := s.endBlock()
+ b.Kind = ssa.BlockIf
+ b.Control = el
+ // In theory, we should set b.Likely here based on context.
+ // However, gc only gives us likeliness hints
+ // in a single place, for plain OIF statements,
+ // and passing around context is finnicky, so don't bother for now.
+
+ bRight := s.f.NewBlock(ssa.BlockPlain)
+ bResult := s.f.NewBlock(ssa.BlockPlain)
+ if n.Op == OANDAND {
+ b.AddEdgeTo(bRight)
+ b.AddEdgeTo(bResult)
+ } else if n.Op == OOROR {
+ b.AddEdgeTo(bResult)
+ b.AddEdgeTo(bRight)
+ }
+
+ s.startBlock(bRight)
+ er := s.expr(n.Right)
+ s.vars[n] = er
+
+ b = s.endBlock()
+ b.AddEdgeTo(bResult)
+
+ s.startBlock(bResult)
+ return s.variable(n, Types[TBOOL])
+
+ // unary ops
+ case OMINUS:
+ a := s.expr(n.Left)
+ if n.Type.IsComplex() {
+ tp := floatForComplex(n.Type)
+ negop := s.ssaOp(n.Op, tp)
+ return s.newValue2(ssa.OpComplexMake, n.Type,
+ s.newValue1(negop, tp, s.newValue1(ssa.OpComplexReal, tp, a)),
+ s.newValue1(negop, tp, s.newValue1(ssa.OpComplexImag, tp, a)))
+ }
+ return s.newValue1(s.ssaOp(n.Op, n.Type), a.Type, a)
+ case ONOT, OCOM, OIMAG, OREAL:
+ a := s.expr(n.Left)
+ return s.newValue1(s.ssaOp(n.Op, n.Type), a.Type, a)
+ case OPLUS:
+ return s.expr(n.Left)
+
+ case OADDR:
+ return s.addr(n.Left)
+
+ case OCHECKNIL:
+ p := s.expr(n.Left)
+ s.nilCheck(p)
+ return p
+
+ case OINDREG:
+ if int(n.Reg) != Thearch.REGSP {
+ s.Unimplementedf("OINDREG of non-SP register %s in expr: %v", obj.Rconv(int(n.Reg)), n)
+ return nil
+ }
+ addr := s.entryNewValue1I(ssa.OpOffPtr, Ptrto(n.Type), n.Xoffset, s.sp)
+ return s.newValue2(ssa.OpLoad, n.Type, addr, s.mem())
+
+ case OIND:
+ p := s.expr(n.Left)
+ s.nilCheck(p)
+ return s.newValue2(ssa.OpLoad, n.Type, p, s.mem())
+
+ case ODOT:
+ v := s.expr(n.Left)
+ return s.newValue1I(ssa.OpStructSelect, n.Type, n.Xoffset, v)
+
+ case ODOTPTR:
+ p := s.expr(n.Left)
+ s.nilCheck(p)
+ p = s.newValue2(ssa.OpAddPtr, p.Type, p, s.constIntPtr(Types[TUINTPTR], n.Xoffset))
+ return s.newValue2(ssa.OpLoad, n.Type, p, s.mem())
+
+ case OINDEX:
+ if n.Left.Type.Bound >= 0 { // array or string
+ a := s.expr(n.Left)
+ i := s.expr(n.Right)
+ i = s.extendIndex(i)
+ var elemtype *Type
+ var len *ssa.Value
+ if n.Left.Type.IsString() {
+ len = s.newValue1(ssa.OpStringLen, Types[TINT], a)
+ elemtype = Types[TUINT8]
+ } else {
+ len = s.constInt(Types[TINT], n.Left.Type.Bound)
+ elemtype = n.Left.Type.Type
+ }
+ if !n.Bounded {
+ s.boundsCheck(i, len)
+ }
+ return s.newValue2(ssa.OpArrayIndex, elemtype, a, i)
+ } else { // slice
+ p := s.addr(n)
+ return s.newValue2(ssa.OpLoad, n.Left.Type.Type, p, s.mem())
+ }
+
+ case OLEN, OCAP:
+ switch {
+ case n.Left.Type.IsSlice():
+ op := ssa.OpSliceLen
+ if n.Op == OCAP {
+ op = ssa.OpSliceCap
+ }
+ return s.newValue1(op, Types[TINT], s.expr(n.Left))
+ case n.Left.Type.IsString(): // string; not reachable for OCAP
+ return s.newValue1(ssa.OpStringLen, Types[TINT], s.expr(n.Left))
+ case n.Left.Type.IsMap(), n.Left.Type.IsChan():
+ return s.referenceTypeBuiltin(n, s.expr(n.Left))
+ default: // array
+ return s.constInt(Types[TINT], n.Left.Type.Bound)
+ }
+
+ case OSPTR:
+ a := s.expr(n.Left)
+ if n.Left.Type.IsSlice() {
+ return s.newValue1(ssa.OpSlicePtr, n.Type, a)
+ } else {
+ return s.newValue1(ssa.OpStringPtr, n.Type, a)
+ }
+
+ case OITAB:
+ a := s.expr(n.Left)
+ return s.newValue1(ssa.OpITab, n.Type, a)
+
+ case OEFACE:
+ tab := s.expr(n.Left)
+ data := s.expr(n.Right)
+ return s.newValue2(ssa.OpIMake, n.Type, tab, data)
+
+ case OSLICESTR:
+ // Evaluate the string once.
+ str := s.expr(n.Left)
+ ptr := s.newValue1(ssa.OpStringPtr, Ptrto(Types[TUINT8]), str)
+ len := s.newValue1(ssa.OpStringLen, Types[TINT], str)
+ zero := s.constInt(Types[TINT], 0)
+
+ // Evaluate the slice indexes.
+ var low, high *ssa.Value
+ if n.Right.Left == nil {
+ low = zero
+ } else {
+ low = s.extendIndex(s.expr(n.Right.Left))
+ }
+ if n.Right.Right == nil {
+ high = len
+ } else {
+ high = s.extendIndex(s.expr(n.Right.Right))
+ }
+
+ // Panic if slice indices are not in bounds.
+ s.sliceBoundsCheck(low, high)
+ s.sliceBoundsCheck(high, len)
+
+ // Generate the following code assuming that indexes are in bounds.
+ // The conditional is to make sure that we don't generate a string
+ // that points to the next object in memory.
+ // rlen = (SubPtr high low)
+ // p = ptr
+ // if rlen != 0 {
+ // p = (AddPtr ptr low)
+ // }
+ // result = (StringMake p size)
+ rlen := s.newValue2(ssa.OpSubPtr, Types[TINT], high, low)
+
+ // Use n as the "variable" for p.
+ s.vars[n] = ptr
+
+ // Generate code to test the resulting slice length.
+ var cmp *ssa.Value
+ if s.config.IntSize == 8 {
+ cmp = s.newValue2(ssa.OpNeq64, Types[TBOOL], rlen, zero)
+ } else {
+ cmp = s.newValue2(ssa.OpNeq32, Types[TBOOL], rlen, zero)
+ }
+
+ b := s.endBlock()
+ b.Kind = ssa.BlockIf
+ b.Likely = ssa.BranchLikely
+ b.Control = cmp
+
+ // Generate code for non-zero length slice case.
+ nz := s.f.NewBlock(ssa.BlockPlain)
+ b.AddEdgeTo(nz)
+ s.startBlock(nz)
+ s.vars[n] = s.newValue2(ssa.OpAddPtr, Ptrto(Types[TUINT8]), ptr, low)
+ s.endBlock()
+
+ // All done.
+ merge := s.f.NewBlock(ssa.BlockPlain)
+ b.AddEdgeTo(merge)
+ nz.AddEdgeTo(merge)
+ s.startBlock(merge)
+ return s.newValue2(ssa.OpStringMake, Types[TSTRING], s.variable(n, Ptrto(Types[TUINT8])), rlen)
+
+ case OCALLFUNC, OCALLMETH:
+ left := n.Left
+ static := left.Op == ONAME && left.Class == PFUNC
+
+ if n.Op == OCALLMETH {
+ // Rewrite to an OCALLFUNC: (p.f)(...) becomes (f)(p, ...)
+ // Take care not to modify the original AST.
+ if left.Op != ODOTMETH {
- Fatal("non-static data marked as static: %v\n\n", n, f)
++ Fatalf("OCALLMETH: n.Left not an ODOTMETH: %v", left)
+ }
+
+ newLeft := *left.Right
+ newLeft.Type = left.Type
+ if newLeft.Op == ONAME {
+ newLeft.Class = PFUNC
+ }
+ left = &newLeft
+ static = true
+ }
+
+ // evaluate closure
+ var closure *ssa.Value
+ if !static {
+ closure = s.expr(left)
+ }
+
+ // run all argument assignments
+ s.stmtList(n.List)
+
+ bNext := s.f.NewBlock(ssa.BlockPlain)
+ var call *ssa.Value
+ if static {
+ call = s.newValue1A(ssa.OpStaticCall, ssa.TypeMem, left.Sym, s.mem())
+ } else {
+ entry := s.newValue2(ssa.OpLoad, Types[TUINTPTR], closure, s.mem())
+ call = s.newValue3(ssa.OpClosureCall, ssa.TypeMem, entry, closure, s.mem())
+ }
+ dowidth(left.Type)
+ call.AuxInt = left.Type.Argwid // call operations carry the argsize of the callee along with them
+ s.vars[&memvar] = call
+ b := s.endBlock()
+ b.Kind = ssa.BlockCall
+ b.Control = call
+ b.AddEdgeTo(bNext)
+ b.AddEdgeTo(s.exit)
+
+ // read result from stack at the start of the fallthrough block
+ s.startBlock(bNext)
+ var titer Iter
+ fp := Structfirst(&titer, Getoutarg(left.Type))
+ if fp == nil {
+ // CALLFUNC has no return value. Continue with the next statement.
+ return nil
+ }
+ a := s.entryNewValue1I(ssa.OpOffPtr, Ptrto(fp.Type), fp.Width, s.sp)
+ return s.newValue2(ssa.OpLoad, fp.Type, a, call)
+
+ case OGETG:
+ return s.newValue0(ssa.OpGetG, n.Type)
+
+ default:
+ s.Unimplementedf("unhandled expr %s", opnames[n.Op])
+ return nil
+ }
+}
+
+func (s *state) assign(op uint8, left *Node, right *Node) {
+ if left.Op == ONAME && isblank(left) {
+ if right != nil {
+ s.expr(right)
+ }
+ return
+ }
+ // TODO: do write barrier
+ // if op == OASWB
+ t := left.Type
+ dowidth(t)
+ var val *ssa.Value
+ if right == nil {
+ // right == nil means use the zero value of the assigned type.
+ if !canSSA(left) {
+ // if we can't ssa this memory, treat it as just zeroing out the backing memory
+ addr := s.addr(left)
+ if left.Op == ONAME {
+ s.vars[&memvar] = s.newValue1A(ssa.OpVarDef, ssa.TypeMem, left, s.mem())
+ }
+ s.vars[&memvar] = s.newValue2I(ssa.OpZero, ssa.TypeMem, t.Size(), addr, s.mem())
+ return
+ }
+ val = s.zeroVal(t)
+ } else {
+ val = s.expr(right)
+ }
+ if left.Op == ONAME && canSSA(left) {
+ // Update variable assignment.
+ s.vars[left] = val
+ return
+ }
+ // not ssa-able. Treat as a store.
+ addr := s.addr(left)
+ if left.Op == ONAME {
+ s.vars[&memvar] = s.newValue1A(ssa.OpVarDef, ssa.TypeMem, left, s.mem())
+ }
+ s.vars[&memvar] = s.newValue3I(ssa.OpStore, ssa.TypeMem, t.Size(), addr, val, s.mem())
+}
+
+// zeroVal returns the zero value for type t.
+func (s *state) zeroVal(t *Type) *ssa.Value {
+ switch {
+ case t.IsInteger():
+ switch t.Size() {
+ case 1:
+ return s.constInt8(t, 0)
+ case 2:
+ return s.constInt16(t, 0)
+ case 4:
+ return s.constInt32(t, 0)
+ case 8:
+ return s.constInt64(t, 0)
+ default:
+ s.Fatalf("bad sized integer type %s", t)
+ }
+ case t.IsFloat():
+ switch t.Size() {
+ case 4:
+ return s.constFloat32(t, 0)
+ case 8:
+ return s.constFloat64(t, 0)
+ default:
+ s.Fatalf("bad sized float type %s", t)
+ }
+ case t.IsComplex():
+ switch t.Size() {
+ case 8:
+ z := s.constFloat32(Types[TFLOAT32], 0)
+ return s.entryNewValue2(ssa.OpComplexMake, t, z, z)
+ case 16:
+ z := s.constFloat64(Types[TFLOAT64], 0)
+ return s.entryNewValue2(ssa.OpComplexMake, t, z, z)
+ default:
+ s.Fatalf("bad sized complex type %s", t)
+ }
+
+ case t.IsString():
+ return s.entryNewValue0A(ssa.OpConstString, t, "")
+ case t.IsPtr():
+ return s.entryNewValue0(ssa.OpConstNil, t)
+ case t.IsBoolean():
+ return s.entryNewValue0I(ssa.OpConstBool, Types[TBOOL], 0) // 0 = false
+ case t.IsInterface():
+ return s.entryNewValue0(ssa.OpConstInterface, t)
+ case t.IsSlice():
+ return s.entryNewValue0(ssa.OpConstSlice, t)
+ }
+ s.Unimplementedf("zero for type %v not implemented", t)
+ return nil
+}
+
+// etypesign returns the signed-ness of e, for integer/pointer etypes.
+// -1 means signed, +1 means unsigned, 0 means non-integer/non-pointer.
+func etypesign(e uint8) int8 {
+ switch e {
+ case TINT8, TINT16, TINT32, TINT64, TINT:
+ return -1
+ case TUINT8, TUINT16, TUINT32, TUINT64, TUINT, TUINTPTR, TUNSAFEPTR:
+ return +1
+ }
+ return 0
+}
+
+// addr converts the address of the expression n to SSA, adds it to s and returns the SSA result.
+// The value that the returned Value represents is guaranteed to be non-nil.
+func (s *state) addr(n *Node) *ssa.Value {
+ switch n.Op {
+ case ONAME:
+ switch n.Class {
+ case PEXTERN:
+ // global variable
+ aux := &ssa.ExternSymbol{n.Type, n.Sym}
+ v := s.entryNewValue1A(ssa.OpAddr, Ptrto(n.Type), aux, s.sb)
+ // TODO: Make OpAddr use AuxInt as well as Aux.
+ if n.Xoffset != 0 {
+ v = s.entryNewValue1I(ssa.OpOffPtr, v.Type, n.Xoffset, v)
+ }
+ return v
+ case PPARAM, PPARAMOUT:
+ // parameter/result slot or local variable
+ v := s.decladdrs[n]
+ if v == nil {
+ if flag_race != 0 && n.String() == ".fp" {
+ s.Unimplementedf("race detector mishandles nodfp")
+ }
+ s.Fatalf("addr of undeclared ONAME %v. declared: %v", n, s.decladdrs)
+ }
+ return v
+ case PAUTO:
+ // We need to regenerate the address of autos
+ // at every use. This prevents LEA instructions
+ // from occurring before the corresponding VarDef
+ // op and confusing the liveness analysis into thinking
+ // the variable is live at function entry.
+ // TODO: I'm not sure if this really works or we're just
+ // getting lucky. We might need a real dependency edge
+ // between vardef and addr ops.
+ aux := &ssa.AutoSymbol{Typ: n.Type, Node: n}
+ return s.newValue1A(ssa.OpAddr, Ptrto(n.Type), aux, s.sp)
+ case PAUTO | PHEAP, PPARAMREF:
+ return s.expr(n.Name.Heapaddr)
+ default:
+ s.Unimplementedf("variable address class %v not implemented", n.Class)
+ return nil
+ }
+ case OINDREG:
+ // indirect off a register
+ // used for storing/loading arguments/returns to/from callees
+ if int(n.Reg) != Thearch.REGSP {
+ s.Unimplementedf("OINDREG of non-SP register %s in addr: %v", obj.Rconv(int(n.Reg)), n)
+ return nil
+ }
+ return s.entryNewValue1I(ssa.OpOffPtr, Ptrto(n.Type), n.Xoffset, s.sp)
+ case OINDEX:
+ if n.Left.Type.IsSlice() {
+ a := s.expr(n.Left)
+ i := s.expr(n.Right)
+ i = s.extendIndex(i)
+ len := s.newValue1(ssa.OpSliceLen, Types[TUINTPTR], a)
+ if !n.Bounded {
+ s.boundsCheck(i, len)
+ }
+ p := s.newValue1(ssa.OpSlicePtr, Ptrto(n.Left.Type.Type), a)
+ return s.newValue2(ssa.OpPtrIndex, Ptrto(n.Left.Type.Type), p, i)
+ } else { // array
+ a := s.addr(n.Left)
+ i := s.expr(n.Right)
+ i = s.extendIndex(i)
+ len := s.constInt(Types[TINT], n.Left.Type.Bound)
+ if !n.Bounded {
+ s.boundsCheck(i, len)
+ }
+ return s.newValue2(ssa.OpPtrIndex, Ptrto(n.Left.Type.Type), a, i)
+ }
+ case OIND:
+ p := s.expr(n.Left)
+ s.nilCheck(p)
+ return p
+ case ODOT:
+ p := s.addr(n.Left)
+ return s.newValue2(ssa.OpAddPtr, p.Type, p, s.constIntPtr(Types[TUINTPTR], n.Xoffset))
+ case ODOTPTR:
+ p := s.expr(n.Left)
+ s.nilCheck(p)
+ return s.newValue2(ssa.OpAddPtr, p.Type, p, s.constIntPtr(Types[TUINTPTR], n.Xoffset))
+ default:
+ s.Unimplementedf("unhandled addr %v", Oconv(int(n.Op), 0))
+ return nil
+ }
+}
+
+// canSSA reports whether n is SSA-able.
+// n must be an ONAME.
+func canSSA(n *Node) bool {
+ if n.Op != ONAME {
+ return false
+ }
+ if n.Addrtaken {
+ return false
+ }
+ if n.Class&PHEAP != 0 {
+ return false
+ }
+ switch n.Class {
+ case PEXTERN, PPARAMOUT, PPARAMREF:
+ return false
+ }
+ return canSSAType(n.Type)
+ // TODO: try to make more variables SSAable?
+}
+
+// canSSA reports whether variables of type t are SSA-able.
+func canSSAType(t *Type) bool {
+ dowidth(t)
+ if t.Width > int64(4*Widthptr) {
+ // 4*Widthptr is an arbitrary constant. We want it
+ // to be at least 3*Widthptr so slices can be registerized.
+ // Too big and we'll introduce too much register pressure.
+ return false
+ }
+ switch t.Etype {
+ case TARRAY:
+ if Isslice(t) {
+ return true
+ }
+ // We can't do arrays because dynamic indexing is
+ // not supported on SSA variables.
+ // TODO: maybe allow if length is <=1? All indexes
+ // are constant? Might be good for the arrays
+ // introduced by the compiler for variadic functions.
+ return false
+ case TSTRUCT:
+ if countfield(t) > 4 {
+ // 4 is an arbitrary constant. Same reasoning
+ // as above, lots of small fields would waste
+ // register space needed by other values.
+ return false
+ }
+ for t1 := t.Type; t1 != nil; t1 = t1.Down {
+ if !canSSAType(t1.Type) {
+ return false
+ }
+ }
+ return false // until it is implemented
+ //return true
+ default:
+ return true
+ }
+}
+
+// nilCheck generates nil pointer checking code.
+// Starts a new block on return, unless nil checks are disabled.
+// Used only for automatically inserted nil checks,
+// not for user code like 'x != nil'.
+func (s *state) nilCheck(ptr *ssa.Value) {
+ if Disable_checknil != 0 {
+ return
+ }
+ c := s.newValue1(ssa.OpIsNonNil, Types[TBOOL], ptr)
+ b := s.endBlock()
+ b.Kind = ssa.BlockIf
+ b.Control = c
+ b.Likely = ssa.BranchLikely
+ bNext := s.f.NewBlock(ssa.BlockPlain)
+ bPanic := s.f.NewBlock(ssa.BlockPlain)
+ b.AddEdgeTo(bNext)
+ b.AddEdgeTo(bPanic)
+ bPanic.AddEdgeTo(s.exit)
+ s.startBlock(bPanic)
+ // TODO: implicit nil checks somehow?
+ s.vars[&memvar] = s.newValue2(ssa.OpPanicNilCheck, ssa.TypeMem, ptr, s.mem())
+ s.endBlock()
+ s.startBlock(bNext)
+}
+
+// boundsCheck generates bounds checking code. Checks if 0 <= idx < len, branches to exit if not.
+// Starts a new block on return.
+func (s *state) boundsCheck(idx, len *ssa.Value) {
+ if Debug['B'] != 0 {
+ return
+ }
+ // TODO: convert index to full width?
+ // TODO: if index is 64-bit and we're compiling to 32-bit, check that high 32 bits are zero.
+
+ // bounds check
+ cmp := s.newValue2(ssa.OpIsInBounds, Types[TBOOL], idx, len)
+ s.check(cmp, ssa.OpPanicIndexCheck)
+}
+
+// sliceBoundsCheck generates slice bounds checking code. Checks if 0 <= idx <= len, branches to exit if not.
+// Starts a new block on return.
+func (s *state) sliceBoundsCheck(idx, len *ssa.Value) {
+ if Debug['B'] != 0 {
+ return
+ }
+ // TODO: convert index to full width?
+ // TODO: if index is 64-bit and we're compiling to 32-bit, check that high 32 bits are zero.
+
+ // bounds check
+ cmp := s.newValue2(ssa.OpIsSliceInBounds, Types[TBOOL], idx, len)
+ s.check(cmp, ssa.OpPanicSliceCheck)
+}
+
+// If cmp (a bool) is true, panic using the given op.
+func (s *state) check(cmp *ssa.Value, panicOp ssa.Op) {
+ b := s.endBlock()
+ b.Kind = ssa.BlockIf
+ b.Control = cmp
+ b.Likely = ssa.BranchLikely
+ bNext := s.f.NewBlock(ssa.BlockPlain)
+ bPanic := s.f.NewBlock(ssa.BlockPlain)
+ b.AddEdgeTo(bNext)
+ b.AddEdgeTo(bPanic)
+ bPanic.AddEdgeTo(s.exit)
+ s.startBlock(bPanic)
+ // The panic check takes/returns memory to ensure that the right
+ // memory state is observed if the panic happens.
+ s.vars[&memvar] = s.newValue1(panicOp, ssa.TypeMem, s.mem())
+ s.endBlock()
+ s.startBlock(bNext)
+}
+
+type u2fcvtTab struct {
+ geq, cvt2F, and, rsh, or, add ssa.Op
+ one func(*state, ssa.Type, int64) *ssa.Value
+}
+
+var u64_f64 u2fcvtTab = u2fcvtTab{
+ geq: ssa.OpGeq64,
+ cvt2F: ssa.OpCvt64to64F,
+ and: ssa.OpAnd64,
+ rsh: ssa.OpRsh64Ux64,
+ or: ssa.OpOr64,
+ add: ssa.OpAdd64F,
+ one: (*state).constInt64,
+}
+
+var u64_f32 u2fcvtTab = u2fcvtTab{
+ geq: ssa.OpGeq64,
+ cvt2F: ssa.OpCvt64to32F,
+ and: ssa.OpAnd64,
+ rsh: ssa.OpRsh64Ux64,
+ or: ssa.OpOr64,
+ add: ssa.OpAdd32F,
+ one: (*state).constInt64,
+}
+
+// Excess generality on a machine with 64-bit integer registers.
+// Not used on AMD64.
+var u32_f32 u2fcvtTab = u2fcvtTab{
+ geq: ssa.OpGeq32,
+ cvt2F: ssa.OpCvt32to32F,
+ and: ssa.OpAnd32,
+ rsh: ssa.OpRsh32Ux32,
+ or: ssa.OpOr32,
+ add: ssa.OpAdd32F,
+ one: func(s *state, t ssa.Type, x int64) *ssa.Value {
+ return s.constInt32(t, int32(x))
+ },
+}
+
+func (s *state) uint64Tofloat64(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+ return s.uintTofloat(&u64_f64, n, x, ft, tt)
+}
+
+func (s *state) uint64Tofloat32(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+ return s.uintTofloat(&u64_f32, n, x, ft, tt)
+}
+
+func (s *state) uintTofloat(cvttab *u2fcvtTab, n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+ // if x >= 0 {
+ // result = (floatY) x
+ // } else {
+ // y = uintX(x) ; y = x & 1
+ // z = uintX(x) ; z = z >> 1
+ // z = z >> 1
+ // z = z | y
+ // result = floatY(z)
+ // result = result + result
+ // }
+ //
+ // Code borrowed from old code generator.
+ // What's going on: large 64-bit "unsigned" looks like
+ // negative number to hardware's integer-to-float
+ // conversion. However, because the mantissa is only
+ // 63 bits, we don't need the LSB, so instead we do an
+ // unsigned right shift (divide by two), convert, and
+ // double. However, before we do that, we need to be
+ // sure that we do not lose a "1" if that made the
+ // difference in the resulting rounding. Therefore, we
+ // preserve it, and OR (not ADD) it back in. The case
+ // that matters is when the eleven discarded bits are
+ // equal to 10000000001; that rounds up, and the 1 cannot
+ // be lost else it would round down if the LSB of the
+ // candidate mantissa is 0.
+ cmp := s.newValue2(cvttab.geq, Types[TBOOL], x, s.zeroVal(ft))
+ b := s.endBlock()
+ b.Kind = ssa.BlockIf
+ b.Control = cmp
+ b.Likely = ssa.BranchLikely
+
+ bThen := s.f.NewBlock(ssa.BlockPlain)
+ bElse := s.f.NewBlock(ssa.BlockPlain)
+ bAfter := s.f.NewBlock(ssa.BlockPlain)
+
+ b.AddEdgeTo(bThen)
+ s.startBlock(bThen)
+ a0 := s.newValue1(cvttab.cvt2F, tt, x)
+ s.vars[n] = a0
+ s.endBlock()
+ bThen.AddEdgeTo(bAfter)
+
+ b.AddEdgeTo(bElse)
+ s.startBlock(bElse)
+ one := cvttab.one(s, ft, 1)
+ y := s.newValue2(cvttab.and, ft, x, one)
+ z := s.newValue2(cvttab.rsh, ft, x, one)
+ z = s.newValue2(cvttab.or, ft, z, y)
+ a := s.newValue1(cvttab.cvt2F, tt, z)
+ a1 := s.newValue2(cvttab.add, tt, a, a)
+ s.vars[n] = a1
+ s.endBlock()
+ bElse.AddEdgeTo(bAfter)
+
+ s.startBlock(bAfter)
+ return s.variable(n, n.Type)
+}
+
+// referenceTypeBuiltin generates code for the len/cap builtins for maps and channels.
+func (s *state) referenceTypeBuiltin(n *Node, x *ssa.Value) *ssa.Value {
+ if !n.Left.Type.IsMap() && !n.Left.Type.IsChan() {
+ s.Fatalf("node must be a map or a channel")
+ }
+ // if n == nil {
+ // return 0
+ // } else {
+ // // len
+ // return *((*int)n)
+ // // cap
+ // return *(((*int)n)+1)
+ // }
+ lenType := n.Type
+ nilValue := s.newValue0(ssa.OpConstNil, Types[TUINTPTR])
+ cmp := s.newValue2(ssa.OpEqPtr, Types[TBOOL], x, nilValue)
+ b := s.endBlock()
+ b.Kind = ssa.BlockIf
+ b.Control = cmp
+ b.Likely = ssa.BranchUnlikely
+
+ bThen := s.f.NewBlock(ssa.BlockPlain)
+ bElse := s.f.NewBlock(ssa.BlockPlain)
+ bAfter := s.f.NewBlock(ssa.BlockPlain)
+
+ // length/capacity of a nil map/chan is zero
+ b.AddEdgeTo(bThen)
+ s.startBlock(bThen)
+ s.vars[n] = s.zeroVal(lenType)
+ s.endBlock()
+ bThen.AddEdgeTo(bAfter)
+
+ b.AddEdgeTo(bElse)
+ s.startBlock(bElse)
+ if n.Op == OLEN {
+ // length is stored in the first word for map/chan
+ s.vars[n] = s.newValue2(ssa.OpLoad, lenType, x, s.mem())
+ } else if n.Op == OCAP {
+ // capacity is stored in the second word for chan
+ sw := s.newValue1I(ssa.OpOffPtr, lenType.PtrTo(), lenType.Width, x)
+ s.vars[n] = s.newValue2(ssa.OpLoad, lenType, sw, s.mem())
+ } else {
+ s.Fatalf("op must be OLEN or OCAP")
+ }
+ s.endBlock()
+ bElse.AddEdgeTo(bAfter)
+
+ s.startBlock(bAfter)
+ return s.variable(n, lenType)
+}
+
+type f2uCvtTab struct {
+ ltf, cvt2U, subf ssa.Op
+ value func(*state, ssa.Type, float64) *ssa.Value
+}
+
+var f32_u64 f2uCvtTab = f2uCvtTab{
+ ltf: ssa.OpLess32F,
+ cvt2U: ssa.OpCvt32Fto64,
+ subf: ssa.OpSub32F,
+ value: (*state).constFloat32,
+}
+
+var f64_u64 f2uCvtTab = f2uCvtTab{
+ ltf: ssa.OpLess64F,
+ cvt2U: ssa.OpCvt64Fto64,
+ subf: ssa.OpSub64F,
+ value: (*state).constFloat64,
+}
+
+func (s *state) float32ToUint64(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+ return s.floatToUint(&f32_u64, n, x, ft, tt)
+}
+func (s *state) float64ToUint64(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+ return s.floatToUint(&f64_u64, n, x, ft, tt)
+}
+
+func (s *state) floatToUint(cvttab *f2uCvtTab, n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+ // if x < 9223372036854775808.0 {
+ // result = uintY(x)
+ // } else {
+ // y = x - 9223372036854775808.0
+ // z = uintY(y)
+ // result = z | -9223372036854775808
+ // }
+ twoToThe63 := cvttab.value(s, ft, 9223372036854775808.0)
+ cmp := s.newValue2(cvttab.ltf, Types[TBOOL], x, twoToThe63)
+ b := s.endBlock()
+ b.Kind = ssa.BlockIf
+ b.Control = cmp
+ b.Likely = ssa.BranchLikely
+
+ bThen := s.f.NewBlock(ssa.BlockPlain)
+ bElse := s.f.NewBlock(ssa.BlockPlain)
+ bAfter := s.f.NewBlock(ssa.BlockPlain)
+
+ b.AddEdgeTo(bThen)
+ s.startBlock(bThen)
+ a0 := s.newValue1(cvttab.cvt2U, tt, x)
+ s.vars[n] = a0
+ s.endBlock()
+ bThen.AddEdgeTo(bAfter)
+
+ b.AddEdgeTo(bElse)
+ s.startBlock(bElse)
+ y := s.newValue2(cvttab.subf, ft, x, twoToThe63)
+ y = s.newValue1(cvttab.cvt2U, tt, y)
+ z := s.constInt64(tt, -9223372036854775808)
+ a1 := s.newValue2(ssa.OpOr64, tt, y, z)
+ s.vars[n] = a1
+ s.endBlock()
+ bElse.AddEdgeTo(bAfter)
+
+ s.startBlock(bAfter)
+ return s.variable(n, n.Type)
+}
+
+// checkgoto checks that a goto from from to to does not
+// jump into a block or jump over variable declarations.
+// It is a copy of checkgoto in the pre-SSA backend,
+// modified only for line number handling.
+// TODO: document how this works and why it is designed the way it is.
+func (s *state) checkgoto(from *Node, to *Node) {
+ if from.Sym == to.Sym {
+ return
+ }
+
+ nf := 0
+ for fs := from.Sym; fs != nil; fs = fs.Link {
+ nf++
+ }
+ nt := 0
+ for fs := to.Sym; fs != nil; fs = fs.Link {
+ nt++
+ }
+ fs := from.Sym
+ for ; nf > nt; nf-- {
+ fs = fs.Link
+ }
+ if fs != to.Sym {
+ // decide what to complain about.
+ // prefer to complain about 'into block' over declarations,
+ // so scan backward to find most recent block or else dcl.
+ var block *Sym
+
+ var dcl *Sym
+ ts := to.Sym
+ for ; nt > nf; nt-- {
+ if ts.Pkg == nil {
+ block = ts
+ } else {
+ dcl = ts
+ }
+ ts = ts.Link
+ }
+
+ for ts != fs {
+ if ts.Pkg == nil {
+ block = ts
+ } else {
+ dcl = ts
+ }
+ ts = ts.Link
+ fs = fs.Link
+ }
+
+ lno := int(from.Left.Lineno)
+ if block != nil {
+ yyerrorl(lno, "goto %v jumps into block starting at %v", from.Left.Sym, Ctxt.Line(int(block.Lastlineno)))
+ } else {
+ yyerrorl(lno, "goto %v jumps over declaration of %v at %v", from.Left.Sym, dcl, Ctxt.Line(int(dcl.Lastlineno)))
+ }
+ }
+}
+
+// variable returns the value of a variable at the current location.
+func (s *state) variable(name *Node, t ssa.Type) *ssa.Value {
+ v := s.vars[name]
+ if v == nil {
+ // TODO: get type? Take Sym as arg?
+ v = s.newValue0A(ssa.OpFwdRef, t, name)
+ s.vars[name] = v
+ }
+ return v
+}
+
+func (s *state) mem() *ssa.Value {
+ return s.variable(&memvar, ssa.TypeMem)
+}
+
+func (s *state) linkForwardReferences() {
+ // Build ssa graph. Each variable on its first use in a basic block
+ // leaves a FwdRef in that block representing the incoming value
+ // of that variable. This function links that ref up with possible definitions,
+ // inserting Phi values as needed. This is essentially the algorithm
+ // described by Brau, Buchwald, Hack, Leißa, Mallon, and Zwinkau:
+ // http://pp.info.uni-karlsruhe.de/uploads/publikationen/braun13cc.pdf
+ for _, b := range s.f.Blocks {
+ for _, v := range b.Values {
+ if v.Op != ssa.OpFwdRef {
+ continue
+ }
+ name := v.Aux.(*Node)
+ v.Op = ssa.OpCopy
+ v.Aux = nil
+ v.SetArgs1(s.lookupVarIncoming(b, v.Type, name))
+ }
+ }
+}
+
+// lookupVarIncoming finds the variable's value at the start of block b.
+func (s *state) lookupVarIncoming(b *ssa.Block, t ssa.Type, name *Node) *ssa.Value {
+ // TODO(khr): have lookupVarIncoming overwrite the fwdRef or copy it
+ // will be used in, instead of having the result used in a copy value.
+ if b == s.f.Entry {
+ if name == &memvar {
+ return s.startmem
+ }
+ // variable is live at the entry block. Load it.
+ addr := s.decladdrs[name]
+ if addr == nil {
+ // TODO: closure args reach here.
+ s.Unimplementedf("unhandled closure arg")
+ }
+ if _, ok := addr.Aux.(*ssa.ArgSymbol); !ok {
+ s.Fatalf("variable live at start of function %s is not an argument %s", b.Func.Name, name)
+ }
+ return s.entryNewValue2(ssa.OpLoad, t, addr, s.startmem)
+ }
+ var vals []*ssa.Value
+ for _, p := range b.Preds {
+ vals = append(vals, s.lookupVarOutgoing(p, t, name))
+ }
+ if len(vals) == 0 {
+ // This block is dead; we have no predecessors and we're not the entry block.
+ // It doesn't matter what we use here as long as it is well-formed,
+ // so use the default/zero value.
+ if name == &memvar {
+ return s.startmem
+ }
+ return s.zeroVal(name.Type)
+ }
+ v0 := vals[0]
+ for i := 1; i < len(vals); i++ {
+ if vals[i] != v0 {
+ // need a phi value
+ v := b.NewValue0(s.peekLine(), ssa.OpPhi, t)
+ v.AddArgs(vals...)
+ return v
+ }
+ }
+ return v0
+}
+
+// lookupVarOutgoing finds the variable's value at the end of block b.
+func (s *state) lookupVarOutgoing(b *ssa.Block, t ssa.Type, name *Node) *ssa.Value {
+ m := s.defvars[b.ID]
+ if v, ok := m[name]; ok {
+ return v
+ }
+ // The variable is not defined by b and we haven't
+ // looked it up yet. Generate v, a copy value which
+ // will be the outgoing value of the variable. Then
+ // look up w, the incoming value of the variable.
+ // Make v = copy(w). We need the extra copy to
+ // prevent infinite recursion when looking up the
+ // incoming value of the variable.
+ v := b.NewValue0(s.peekLine(), ssa.OpCopy, t)
+ m[name] = v
+ v.AddArg(s.lookupVarIncoming(b, t, name))
+ return v
+}
+
+// TODO: the above mutually recursive functions can lead to very deep stacks. Fix that.
+
+// an unresolved branch
+type branch struct {
+ p *obj.Prog // branch instruction
+ b *ssa.Block // target
+}
+
+type genState struct {
+ // branches remembers all the branch instructions we've seen
+ // and where they would like to go.
+ branches []branch
+
+ // bstart remembers where each block starts (indexed by block ID)
+ bstart []*obj.Prog
+
+ // deferBranches remembers all the defer branches we've seen.
+ deferBranches []*obj.Prog
+
+ // deferTarget remembers the (last) deferreturn call site.
+ deferTarget *obj.Prog
+}
+
+// genssa appends entries to ptxt for each instruction in f.
+// gcargs and gclocals are filled in with pointer maps for the frame.
+func genssa(f *ssa.Func, ptxt *obj.Prog, gcargs, gclocals *Sym) {
+ var s genState
+
+ e := f.Config.Frontend().(*ssaExport)
+ // We're about to emit a bunch of Progs.
+ // Since the only way to get here is to explicitly request it,
+ // just fail on unimplemented instead of trying to unwind our mess.
+ e.mustImplement = true
+
+ // Remember where each block starts.
+ s.bstart = make([]*obj.Prog, f.NumBlocks())
+
+ var valueProgs map[*obj.Prog]*ssa.Value
+ var blockProgs map[*obj.Prog]*ssa.Block
+ const logProgs = true
+ if logProgs {
+ valueProgs = make(map[*obj.Prog]*ssa.Value, f.NumValues())
+ blockProgs = make(map[*obj.Prog]*ssa.Block, f.NumBlocks())
+ f.Logf("genssa %s\n", f.Name)
+ blockProgs[Pc] = f.Blocks[0]
+ }
+
+ // Emit basic blocks
+ for i, b := range f.Blocks {
+ s.bstart[b.ID] = Pc
+ // Emit values in block
+ for _, v := range b.Values {
+ x := Pc
+ s.genValue(v)
+ if logProgs {
+ for ; x != Pc; x = x.Link {
+ valueProgs[x] = v
+ }
+ }
+ }
+ // Emit control flow instructions for block
+ var next *ssa.Block
+ if i < len(f.Blocks)-1 {
+ next = f.Blocks[i+1]
+ }
+ x := Pc
+ s.genBlock(b, next)
+ if logProgs {
+ for ; x != Pc; x = x.Link {
+ blockProgs[x] = b
+ }
+ }
+ }
+
+ // Resolve branches
+ for _, br := range s.branches {
+ br.p.To.Val = s.bstart[br.b.ID]
+ }
+ if s.deferBranches != nil && s.deferTarget == nil {
+ // This can happen when the function has a defer but
+ // no return (because it has an infinite loop).
+ s.deferReturn()
+ Prog(obj.ARET)
+ }
+ for _, p := range s.deferBranches {
+ p.To.Val = s.deferTarget
+ }
+
+ Pc.As = obj.ARET // overwrite AEND
+
+ if logProgs {
+ for p := ptxt; p != nil; p = p.Link {
+ var s string
+ if v, ok := valueProgs[p]; ok {
+ s = v.String()
+ } else if b, ok := blockProgs[p]; ok {
+ s = b.String()
+ } else {
+ s = " " // most value and branch strings are 2-3 characters long
+ }
+ f.Logf("%s\t%s\n", s, p)
+ }
+ if f.Config.HTML != nil {
+ saved := ptxt.Ctxt.LineHist.PrintFilenameOnly
+ ptxt.Ctxt.LineHist.PrintFilenameOnly = true
+ var buf bytes.Buffer
+ buf.WriteString("<code>")
+ buf.WriteString("<dl class=\"ssa-gen\">")
+ for p := ptxt; p != nil; p = p.Link {
+ buf.WriteString("<dt class=\"ssa-prog-src\">")
+ if v, ok := valueProgs[p]; ok {
+ buf.WriteString(v.HTML())
+ } else if b, ok := blockProgs[p]; ok {
+ buf.WriteString(b.HTML())
+ }
+ buf.WriteString("</dt>")
+ buf.WriteString("<dd class=\"ssa-prog\">")
+ buf.WriteString(html.EscapeString(p.String()))
+ buf.WriteString("</dd>")
+ buf.WriteString("</li>")
+ }
+ buf.WriteString("</dl>")
+ buf.WriteString("</code>")
+ f.Config.HTML.WriteColumn("genssa", buf.String())
+ ptxt.Ctxt.LineHist.PrintFilenameOnly = saved
+ }
+ }
+
+ // Emit static data
+ if f.StaticData != nil {
+ for _, n := range f.StaticData.([]*Node) {
+ if !gen_as_init(n, false) {
- if Hasdefer != 0 {
++ Fatalf("non-static data marked as static: %v\n\n", n, f)
+ }
+ }
+ }
+
+ // Allocate stack frame
+ allocauto(ptxt)
+
+ // Generate gc bitmaps.
+ liveness(Curfn, ptxt, gcargs, gclocals)
+ gcsymdup(gcargs)
+ gcsymdup(gclocals)
+
+ // Add frame prologue. Zero ambiguously live variables.
+ Thearch.Defframe(ptxt)
+ if Debug['f'] != 0 {
+ frame(0)
+ }
+
+ // Remove leftover instrumentation from the instruction stream.
+ removevardef(ptxt)
+
+ f.Config.HTML.Close()
+}
+
+// opregreg emits instructions for
+// dest := dest(To) op src(From)
+// and also returns the created obj.Prog so it
+// may be further adjusted (offset, scale, etc).
+func opregreg(op int, dest, src int16) *obj.Prog {
+ p := Prog(op)
+ p.From.Type = obj.TYPE_REG
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = dest
+ p.From.Reg = src
+ return p
+}
+
+func (s *genState) genValue(v *ssa.Value) {
+ lineno = v.Line
+ switch v.Op {
+ case ssa.OpAMD64ADDQ:
+ // TODO: use addq instead of leaq if target is in the right register.
+ p := Prog(x86.ALEAQ)
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = regnum(v.Args[0])
+ p.From.Scale = 1
+ p.From.Index = regnum(v.Args[1])
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ case ssa.OpAMD64ADDL:
+ p := Prog(x86.ALEAL)
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = regnum(v.Args[0])
+ p.From.Scale = 1
+ p.From.Index = regnum(v.Args[1])
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ case ssa.OpAMD64ADDW:
+ p := Prog(x86.ALEAW)
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = regnum(v.Args[0])
+ p.From.Scale = 1
+ p.From.Index = regnum(v.Args[1])
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ // 2-address opcode arithmetic, symmetric
+ case ssa.OpAMD64ADDB, ssa.OpAMD64ADDSS, ssa.OpAMD64ADDSD,
+ ssa.OpAMD64ANDQ, ssa.OpAMD64ANDL, ssa.OpAMD64ANDW, ssa.OpAMD64ANDB,
+ ssa.OpAMD64ORQ, ssa.OpAMD64ORL, ssa.OpAMD64ORW, ssa.OpAMD64ORB,
+ ssa.OpAMD64XORQ, ssa.OpAMD64XORL, ssa.OpAMD64XORW, ssa.OpAMD64XORB,
+ ssa.OpAMD64MULQ, ssa.OpAMD64MULL, ssa.OpAMD64MULW, ssa.OpAMD64MULB,
+ ssa.OpAMD64MULSS, ssa.OpAMD64MULSD, ssa.OpAMD64PXOR:
+ r := regnum(v)
+ x := regnum(v.Args[0])
+ y := regnum(v.Args[1])
+ if x != r && y != r {
+ opregreg(regMoveByTypeAMD64(v.Type), r, x)
+ x = r
+ }
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_REG
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ if x == r {
+ p.From.Reg = y
+ } else {
+ p.From.Reg = x
+ }
+ // 2-address opcode arithmetic, not symmetric
+ case ssa.OpAMD64SUBQ, ssa.OpAMD64SUBL, ssa.OpAMD64SUBW, ssa.OpAMD64SUBB:
+ r := regnum(v)
+ x := regnum(v.Args[0])
+ y := regnum(v.Args[1])
+ var neg bool
+ if y == r {
+ // compute -(y-x) instead
+ x, y = y, x
+ neg = true
+ }
+ if x != r {
+ opregreg(regMoveByTypeAMD64(v.Type), r, x)
+ }
+ opregreg(v.Op.Asm(), r, y)
+
+ if neg {
+ p := Prog(x86.ANEGQ) // TODO: use correct size? This is mostly a hack until regalloc does 2-address correctly
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ }
+ case ssa.OpAMD64SUBSS, ssa.OpAMD64SUBSD, ssa.OpAMD64DIVSS, ssa.OpAMD64DIVSD:
+ r := regnum(v)
+ x := regnum(v.Args[0])
+ y := regnum(v.Args[1])
+ if y == r && x != r {
+ // r/y := x op r/y, need to preserve x and rewrite to
+ // r/y := r/y op x15
+ x15 := int16(x86.REG_X15)
+ // register move y to x15
+ // register move x to y
+ // rename y with x15
+ opregreg(regMoveByTypeAMD64(v.Type), x15, y)
+ opregreg(regMoveByTypeAMD64(v.Type), r, x)
+ y = x15
+ } else if x != r {
+ opregreg(regMoveByTypeAMD64(v.Type), r, x)
+ }
+ opregreg(v.Op.Asm(), r, y)
+
+ case ssa.OpAMD64DIVQ, ssa.OpAMD64DIVL, ssa.OpAMD64DIVW,
+ ssa.OpAMD64DIVQU, ssa.OpAMD64DIVLU, ssa.OpAMD64DIVWU,
+ ssa.OpAMD64MODQ, ssa.OpAMD64MODL, ssa.OpAMD64MODW,
+ ssa.OpAMD64MODQU, ssa.OpAMD64MODLU, ssa.OpAMD64MODWU:
+
+ // Arg[0] is already in AX as it's the only register we allow
+ // and AX is the only output
+ x := regnum(v.Args[1])
+
+ // CPU faults upon signed overflow, which occurs when most
+ // negative int is divided by -1.
+ var j *obj.Prog
+ if v.Op == ssa.OpAMD64DIVQ || v.Op == ssa.OpAMD64DIVL ||
+ v.Op == ssa.OpAMD64DIVW || v.Op == ssa.OpAMD64MODQ ||
+ v.Op == ssa.OpAMD64MODL || v.Op == ssa.OpAMD64MODW {
+
+ var c *obj.Prog
+ switch v.Op {
+ case ssa.OpAMD64DIVQ, ssa.OpAMD64MODQ:
+ c = Prog(x86.ACMPQ)
+ j = Prog(x86.AJEQ)
+ // go ahead and sign extend to save doing it later
+ Prog(x86.ACQO)
+
+ case ssa.OpAMD64DIVL, ssa.OpAMD64MODL:
+ c = Prog(x86.ACMPL)
+ j = Prog(x86.AJEQ)
+ Prog(x86.ACDQ)
+
+ case ssa.OpAMD64DIVW, ssa.OpAMD64MODW:
+ c = Prog(x86.ACMPW)
+ j = Prog(x86.AJEQ)
+ Prog(x86.ACWD)
+ }
+ c.From.Type = obj.TYPE_REG
+ c.From.Reg = x
+ c.To.Type = obj.TYPE_CONST
+ c.To.Offset = -1
+
+ j.To.Type = obj.TYPE_BRANCH
+
+ }
+
+ // for unsigned ints, we sign extend by setting DX = 0
+ // signed ints were sign extended above
+ if v.Op == ssa.OpAMD64DIVQU || v.Op == ssa.OpAMD64MODQU ||
+ v.Op == ssa.OpAMD64DIVLU || v.Op == ssa.OpAMD64MODLU ||
+ v.Op == ssa.OpAMD64DIVWU || v.Op == ssa.OpAMD64MODWU {
+ c := Prog(x86.AXORQ)
+ c.From.Type = obj.TYPE_REG
+ c.From.Reg = x86.REG_DX
+ c.To.Type = obj.TYPE_REG
+ c.To.Reg = x86.REG_DX
+ }
+
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = x
+
+ // signed division, rest of the check for -1 case
+ if j != nil {
+ j2 := Prog(obj.AJMP)
+ j2.To.Type = obj.TYPE_BRANCH
+
+ var n *obj.Prog
+ if v.Op == ssa.OpAMD64DIVQ || v.Op == ssa.OpAMD64DIVL ||
+ v.Op == ssa.OpAMD64DIVW {
+ // n * -1 = -n
+ n = Prog(x86.ANEGQ)
+ n.To.Type = obj.TYPE_REG
+ n.To.Reg = x86.REG_AX
+ } else {
+ // n % -1 == 0
+ n = Prog(x86.AXORQ)
+ n.From.Type = obj.TYPE_REG
+ n.From.Reg = x86.REG_DX
+ n.To.Type = obj.TYPE_REG
+ n.To.Reg = x86.REG_DX
+ }
+
+ j.To.Val = n
+ j2.To.Val = Pc
+ }
+
+ case ssa.OpAMD64HMULL, ssa.OpAMD64HMULW, ssa.OpAMD64HMULB,
+ ssa.OpAMD64HMULLU, ssa.OpAMD64HMULWU, ssa.OpAMD64HMULBU:
+ // the frontend rewrites constant division by 8/16/32 bit integers into
+ // HMUL by a constant
+
+ // Arg[0] is already in AX as it's the only register we allow
+ // and DX is the only output we care about (the high bits)
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = regnum(v.Args[1])
+
+ // IMULB puts the high portion in AH instead of DL,
+ // so move it to DL for consistency
+ if v.Type.Size() == 1 {
+ m := Prog(x86.AMOVB)
+ m.From.Type = obj.TYPE_REG
+ m.From.Reg = x86.REG_AH
+ m.To.Type = obj.TYPE_REG
+ m.To.Reg = x86.REG_DX
+ }
+
+ case ssa.OpAMD64SHLQ, ssa.OpAMD64SHLL, ssa.OpAMD64SHLW, ssa.OpAMD64SHLB,
+ ssa.OpAMD64SHRQ, ssa.OpAMD64SHRL, ssa.OpAMD64SHRW, ssa.OpAMD64SHRB,
+ ssa.OpAMD64SARQ, ssa.OpAMD64SARL, ssa.OpAMD64SARW, ssa.OpAMD64SARB:
+ x := regnum(v.Args[0])
+ r := regnum(v)
+ if x != r {
+ if r == x86.REG_CX {
+ v.Fatalf("can't implement %s, target and shift both in CX", v.LongString())
+ }
+ p := Prog(regMoveAMD64(v.Type.Size()))
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = x
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ }
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = regnum(v.Args[1]) // should be CX
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ case ssa.OpAMD64ADDQconst, ssa.OpAMD64ADDLconst, ssa.OpAMD64ADDWconst:
+ // TODO: use addq instead of leaq if target is in the right register.
+ var asm int
+ switch v.Op {
+ case ssa.OpAMD64ADDQconst:
+ asm = x86.ALEAQ
+ case ssa.OpAMD64ADDLconst:
+ asm = x86.ALEAL
+ case ssa.OpAMD64ADDWconst:
+ asm = x86.ALEAW
+ }
+ p := Prog(asm)
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = regnum(v.Args[0])
+ p.From.Offset = v.AuxInt
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ case ssa.OpAMD64MULQconst, ssa.OpAMD64MULLconst, ssa.OpAMD64MULWconst, ssa.OpAMD64MULBconst:
+ r := regnum(v)
+ x := regnum(v.Args[0])
+ if r != x {
+ p := Prog(regMoveAMD64(v.Type.Size()))
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = x
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ }
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_CONST
+ p.From.Offset = v.AuxInt
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ // TODO: Teach doasm to compile the three-address multiply imul $c, r1, r2
+ // instead of using the MOVQ above.
+ //p.From3 = new(obj.Addr)
+ //p.From3.Type = obj.TYPE_REG
+ //p.From3.Reg = regnum(v.Args[0])
+ case ssa.OpAMD64ADDBconst,
+ ssa.OpAMD64ANDQconst, ssa.OpAMD64ANDLconst, ssa.OpAMD64ANDWconst, ssa.OpAMD64ANDBconst,
+ ssa.OpAMD64ORQconst, ssa.OpAMD64ORLconst, ssa.OpAMD64ORWconst, ssa.OpAMD64ORBconst,
+ ssa.OpAMD64XORQconst, ssa.OpAMD64XORLconst, ssa.OpAMD64XORWconst, ssa.OpAMD64XORBconst,
+ ssa.OpAMD64SUBQconst, ssa.OpAMD64SUBLconst, ssa.OpAMD64SUBWconst, ssa.OpAMD64SUBBconst,
+ ssa.OpAMD64SHLQconst, ssa.OpAMD64SHLLconst, ssa.OpAMD64SHLWconst, ssa.OpAMD64SHLBconst,
+ ssa.OpAMD64SHRQconst, ssa.OpAMD64SHRLconst, ssa.OpAMD64SHRWconst, ssa.OpAMD64SHRBconst,
+ ssa.OpAMD64SARQconst, ssa.OpAMD64SARLconst, ssa.OpAMD64SARWconst, ssa.OpAMD64SARBconst,
+ ssa.OpAMD64ROLQconst, ssa.OpAMD64ROLLconst, ssa.OpAMD64ROLWconst, ssa.OpAMD64ROLBconst:
+ // This code compensates for the fact that the register allocator
+ // doesn't understand 2-address instructions yet. TODO: fix that.
+ x := regnum(v.Args[0])
+ r := regnum(v)
+ if x != r {
+ p := Prog(regMoveAMD64(v.Type.Size()))
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = x
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ }
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_CONST
+ p.From.Offset = v.AuxInt
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ case ssa.OpAMD64SBBQcarrymask, ssa.OpAMD64SBBLcarrymask:
+ r := regnum(v)
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = r
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ case ssa.OpAMD64LEAQ1, ssa.OpAMD64LEAQ2, ssa.OpAMD64LEAQ4, ssa.OpAMD64LEAQ8:
+ p := Prog(x86.ALEAQ)
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = regnum(v.Args[0])
+ switch v.Op {
+ case ssa.OpAMD64LEAQ1:
+ p.From.Scale = 1
+ case ssa.OpAMD64LEAQ2:
+ p.From.Scale = 2
+ case ssa.OpAMD64LEAQ4:
+ p.From.Scale = 4
+ case ssa.OpAMD64LEAQ8:
+ p.From.Scale = 8
+ }
+ p.From.Index = regnum(v.Args[1])
+ addAux(&p.From, v)
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ case ssa.OpAMD64LEAQ:
+ p := Prog(x86.ALEAQ)
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = regnum(v.Args[0])
+ addAux(&p.From, v)
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ case ssa.OpAMD64CMPQ, ssa.OpAMD64CMPL, ssa.OpAMD64CMPW, ssa.OpAMD64CMPB,
+ ssa.OpAMD64TESTQ, ssa.OpAMD64TESTL, ssa.OpAMD64TESTW, ssa.OpAMD64TESTB:
+ opregreg(v.Op.Asm(), regnum(v.Args[1]), regnum(v.Args[0]))
+ case ssa.OpAMD64UCOMISS, ssa.OpAMD64UCOMISD:
+ // Go assembler has swapped operands for UCOMISx relative to CMP,
+ // must account for that right here.
+ opregreg(v.Op.Asm(), regnum(v.Args[0]), regnum(v.Args[1]))
+ case ssa.OpAMD64CMPQconst, ssa.OpAMD64CMPLconst, ssa.OpAMD64CMPWconst, ssa.OpAMD64CMPBconst,
+ ssa.OpAMD64TESTQconst, ssa.OpAMD64TESTLconst, ssa.OpAMD64TESTWconst, ssa.OpAMD64TESTBconst:
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = regnum(v.Args[0])
+ p.To.Type = obj.TYPE_CONST
+ p.To.Offset = v.AuxInt
+ case ssa.OpAMD64MOVBconst, ssa.OpAMD64MOVWconst, ssa.OpAMD64MOVLconst, ssa.OpAMD64MOVQconst:
+ x := regnum(v)
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_CONST
+ var i int64
+ switch v.Op {
+ case ssa.OpAMD64MOVBconst:
+ i = int64(int8(v.AuxInt))
+ case ssa.OpAMD64MOVWconst:
+ i = int64(int16(v.AuxInt))
+ case ssa.OpAMD64MOVLconst:
+ i = int64(int32(v.AuxInt))
+ case ssa.OpAMD64MOVQconst:
+ i = v.AuxInt
+ }
+ p.From.Offset = i
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = x
+ case ssa.OpAMD64MOVSSconst, ssa.OpAMD64MOVSDconst:
+ x := regnum(v)
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_FCONST
+ p.From.Val = math.Float64frombits(uint64(v.AuxInt))
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = x
+ case ssa.OpAMD64MOVQload, ssa.OpAMD64MOVSSload, ssa.OpAMD64MOVSDload, ssa.OpAMD64MOVLload, ssa.OpAMD64MOVWload, ssa.OpAMD64MOVBload, ssa.OpAMD64MOVBQSXload, ssa.OpAMD64MOVBQZXload:
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = regnum(v.Args[0])
+ addAux(&p.From, v)
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ case ssa.OpAMD64MOVQloadidx8, ssa.OpAMD64MOVSDloadidx8:
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = regnum(v.Args[0])
+ addAux(&p.From, v)
+ p.From.Scale = 8
+ p.From.Index = regnum(v.Args[1])
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ case ssa.OpAMD64MOVSSloadidx4:
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = regnum(v.Args[0])
+ addAux(&p.From, v)
+ p.From.Scale = 4
+ p.From.Index = regnum(v.Args[1])
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ case ssa.OpAMD64MOVQstore, ssa.OpAMD64MOVSSstore, ssa.OpAMD64MOVSDstore, ssa.OpAMD64MOVLstore, ssa.OpAMD64MOVWstore, ssa.OpAMD64MOVBstore:
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = regnum(v.Args[1])
+ p.To.Type = obj.TYPE_MEM
+ p.To.Reg = regnum(v.Args[0])
+ addAux(&p.To, v)
+ case ssa.OpAMD64MOVQstoreidx8, ssa.OpAMD64MOVSDstoreidx8:
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = regnum(v.Args[2])
+ p.To.Type = obj.TYPE_MEM
+ p.To.Reg = regnum(v.Args[0])
+ p.To.Scale = 8
+ p.To.Index = regnum(v.Args[1])
+ addAux(&p.To, v)
+ case ssa.OpAMD64MOVSSstoreidx4:
+ p := Prog(v.Op.Asm())
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = regnum(v.Args[2])
+ p.To.Type = obj.TYPE_MEM
+ p.To.Reg = regnum(v.Args[0])
+ p.To.Scale = 4
+ p.To.Index = regnum(v.Args[1])
+ addAux(&p.To, v)
+ case ssa.OpAMD64MOVLQSX, ssa.OpAMD64MOVWQSX, ssa.OpAMD64MOVBQSX, ssa.OpAMD64MOVLQZX, ssa.OpAMD64MOVWQZX, ssa.OpAMD64MOVBQZX,
+ ssa.OpAMD64CVTSL2SS, ssa.OpAMD64CVTSL2SD, ssa.OpAMD64CVTSQ2SS, ssa.OpAMD64CVTSQ2SD,
+ ssa.OpAMD64CVTTSS2SL, ssa.OpAMD64CVTTSD2SL, ssa.OpAMD64CVTTSS2SQ, ssa.OpAMD64CVTTSD2SQ,
+ ssa.OpAMD64CVTSS2SD, ssa.OpAMD64CVTSD2SS:
+ opregreg(v.Op.Asm(), regnum(v), regnum(v.Args[0]))
+ case ssa.OpAMD64MOVXzero:
+ nb := v.AuxInt
+ offset := int64(0)
+ reg := regnum(v.Args[0])
+ for nb >= 8 {
+ nb, offset = movZero(x86.AMOVQ, 8, nb, offset, reg)
+ }
+ for nb >= 4 {
+ nb, offset = movZero(x86.AMOVL, 4, nb, offset, reg)
+ }
+ for nb >= 2 {
+ nb, offset = movZero(x86.AMOVW, 2, nb, offset, reg)
+ }
+ for nb >= 1 {
+ nb, offset = movZero(x86.AMOVB, 1, nb, offset, reg)
+ }
+ case ssa.OpCopy: // TODO: lower to MOVQ earlier?
+ if v.Type.IsMemory() {
+ return
+ }
+ x := regnum(v.Args[0])
+ y := regnum(v)
+ if x != y {
+ opregreg(regMoveByTypeAMD64(v.Type), y, x)
+ }
+ case ssa.OpLoadReg:
+ if v.Type.IsFlags() {
+ v.Unimplementedf("load flags not implemented: %v", v.LongString())
+ return
+ }
+ p := Prog(movSizeByType(v.Type))
+ n := autoVar(v.Args[0])
+ p.From.Type = obj.TYPE_MEM
+ p.From.Name = obj.NAME_AUTO
+ p.From.Node = n
+ p.From.Sym = Linksym(n.Sym)
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+
+ case ssa.OpStoreReg:
+ if v.Type.IsFlags() {
+ v.Unimplementedf("store flags not implemented: %v", v.LongString())
+ return
+ }
+ p := Prog(movSizeByType(v.Type))
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = regnum(v.Args[0])
+ n := autoVar(v)
+ p.To.Type = obj.TYPE_MEM
+ p.To.Name = obj.NAME_AUTO
+ p.To.Node = n
+ p.To.Sym = Linksym(n.Sym)
+ case ssa.OpPhi:
+ // just check to make sure regalloc and stackalloc did it right
+ if v.Type.IsMemory() {
+ return
+ }
+ f := v.Block.Func
+ loc := f.RegAlloc[v.ID]
+ for _, a := range v.Args {
+ if aloc := f.RegAlloc[a.ID]; aloc != loc { // TODO: .Equal() instead?
+ v.Fatalf("phi arg at different location than phi: %v @ %v, but arg %v @ %v\n%s\n", v, loc, a, aloc, v.Block.Func)
+ }
+ }
+ case ssa.OpConst8, ssa.OpConst16, ssa.OpConst32, ssa.OpConst64, ssa.OpConstString, ssa.OpConstNil, ssa.OpConstBool,
+ ssa.OpConst32F, ssa.OpConst64F:
+ if v.Block.Func.RegAlloc[v.ID] != nil {
+ v.Fatalf("const value %v shouldn't have a location", v)
+ }
+
+ case ssa.OpArg:
+ // memory arg needs no code
+ // TODO: check that only mem arg goes here.
+ case ssa.OpAMD64LoweredPanicNilCheck:
+ if Debug_checknil != 0 && v.Line > 1 { // v.Line==1 in generated wrappers
+ Warnl(int(v.Line), "generated nil check")
+ }
+ // Write to memory address 0. It doesn't matter what we write; use AX.
+ // Input 0 is the pointer we just checked, use it as the destination.
+ r := regnum(v.Args[0])
+ q := Prog(x86.AMOVL)
+ q.From.Type = obj.TYPE_REG
+ q.From.Reg = x86.REG_AX
+ q.To.Type = obj.TYPE_MEM
+ q.To.Reg = r
+ Prog(obj.AUNDEF) // tell plive.go that we never reach here
+ case ssa.OpAMD64LoweredPanicIndexCheck:
+ p := Prog(obj.ACALL)
+ p.To.Type = obj.TYPE_MEM
+ p.To.Name = obj.NAME_EXTERN
+ p.To.Sym = Linksym(Panicindex.Sym)
+ Prog(obj.AUNDEF)
+ case ssa.OpAMD64LoweredPanicSliceCheck:
+ p := Prog(obj.ACALL)
+ p.To.Type = obj.TYPE_MEM
+ p.To.Name = obj.NAME_EXTERN
+ p.To.Sym = Linksym(panicslice.Sym)
+ Prog(obj.AUNDEF)
+ case ssa.OpAMD64LoweredGetG:
+ r := regnum(v)
+ // See the comments in cmd/internal/obj/x86/obj6.go
+ // near CanUse1InsnTLS for a detailed explanation of these instructions.
+ if x86.CanUse1InsnTLS(Ctxt) {
+ // MOVQ (TLS), r
+ p := Prog(x86.AMOVQ)
+ p.From.Type = obj.TYPE_MEM
+ p.From.Reg = x86.REG_TLS
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ } else {
+ // MOVQ TLS, r
+ // MOVQ (r)(TLS*1), r
+ p := Prog(x86.AMOVQ)
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = x86.REG_TLS
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ q := Prog(x86.AMOVQ)
+ q.From.Type = obj.TYPE_MEM
+ q.From.Reg = r
+ q.From.Index = x86.REG_TLS
+ q.From.Scale = 1
+ q.To.Type = obj.TYPE_REG
+ q.To.Reg = r
+ }
+ case ssa.OpAMD64CALLstatic:
+ p := Prog(obj.ACALL)
+ p.To.Type = obj.TYPE_MEM
+ p.To.Name = obj.NAME_EXTERN
+ p.To.Sym = Linksym(v.Aux.(*Sym))
+ if Maxarg < v.AuxInt {
+ Maxarg = v.AuxInt
+ }
+ case ssa.OpAMD64CALLclosure:
+ p := Prog(obj.ACALL)
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v.Args[0])
+ if Maxarg < v.AuxInt {
+ Maxarg = v.AuxInt
+ }
+ case ssa.OpAMD64CALLdefer:
+ p := Prog(obj.ACALL)
+ p.To.Type = obj.TYPE_MEM
+ p.To.Name = obj.NAME_EXTERN
+ p.To.Sym = Linksym(Deferproc.Sym)
+ if Maxarg < v.AuxInt {
+ Maxarg = v.AuxInt
+ }
+ // defer returns in rax:
+ // 0 if we should continue executing
+ // 1 if we should jump to deferreturn call
+ p = Prog(x86.ATESTL)
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = x86.REG_AX
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = x86.REG_AX
+ p = Prog(x86.AJNE)
+ p.To.Type = obj.TYPE_BRANCH
+ s.deferBranches = append(s.deferBranches, p)
+ case ssa.OpAMD64CALLgo:
+ p := Prog(obj.ACALL)
+ p.To.Type = obj.TYPE_MEM
+ p.To.Name = obj.NAME_EXTERN
+ p.To.Sym = Linksym(Newproc.Sym)
+ if Maxarg < v.AuxInt {
+ Maxarg = v.AuxInt
+ }
+ case ssa.OpAMD64NEGQ, ssa.OpAMD64NEGL, ssa.OpAMD64NEGW, ssa.OpAMD64NEGB,
+ ssa.OpAMD64NOTQ, ssa.OpAMD64NOTL, ssa.OpAMD64NOTW, ssa.OpAMD64NOTB:
+ x := regnum(v.Args[0])
+ r := regnum(v)
+ if x != r {
+ p := Prog(regMoveAMD64(v.Type.Size()))
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = x
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ }
+ p := Prog(v.Op.Asm())
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = r
+ case ssa.OpSP, ssa.OpSB:
+ // nothing to do
+ case ssa.OpAMD64SETEQ, ssa.OpAMD64SETNE,
+ ssa.OpAMD64SETL, ssa.OpAMD64SETLE,
+ ssa.OpAMD64SETG, ssa.OpAMD64SETGE,
+ ssa.OpAMD64SETGF, ssa.OpAMD64SETGEF,
+ ssa.OpAMD64SETB, ssa.OpAMD64SETBE,
+ ssa.OpAMD64SETORD, ssa.OpAMD64SETNAN,
+ ssa.OpAMD64SETA, ssa.OpAMD64SETAE:
+ p := Prog(v.Op.Asm())
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+
+ case ssa.OpAMD64SETNEF:
+ p := Prog(v.Op.Asm())
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ q := Prog(x86.ASETPS)
+ q.To.Type = obj.TYPE_REG
+ q.To.Reg = x86.REG_AX
+ // TODO AORQ copied from old code generator, why not AORB?
+ opregreg(x86.AORQ, regnum(v), x86.REG_AX)
+
+ case ssa.OpAMD64SETEQF:
+ p := Prog(v.Op.Asm())
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = regnum(v)
+ q := Prog(x86.ASETPC)
+ q.To.Type = obj.TYPE_REG
+ q.To.Reg = x86.REG_AX
+ // TODO AANDQ copied from old code generator, why not AANDB?
+ opregreg(x86.AANDQ, regnum(v), x86.REG_AX)
+
+ case ssa.OpAMD64InvertFlags:
+ v.Fatalf("InvertFlags should never make it to codegen %v", v)
+ case ssa.OpAMD64REPSTOSQ:
+ p := Prog(x86.AXORL) // TODO: lift out zeroing into its own instruction?
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = x86.REG_AX
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = x86.REG_AX
+ Prog(x86.AREP)
+ Prog(x86.ASTOSQ)
+ case ssa.OpAMD64REPMOVSB:
+ Prog(x86.AREP)
+ Prog(x86.AMOVSB)
+ case ssa.OpVarDef:
+ Gvardef(v.Aux.(*Node))
+ case ssa.OpVarKill:
+ gvarkill(v.Aux.(*Node))
+ default:
+ v.Unimplementedf("genValue not implemented: %s", v.LongString())
+ }
+}
+
+// movSizeByType returns the MOV instruction of the given type.
+func movSizeByType(t ssa.Type) (asm int) {
+ // For x86, there's no difference between reg move opcodes
+ // and memory move opcodes.
+ asm = regMoveByTypeAMD64(t)
+ return
+}
+
+// movZero generates a register indirect move with a 0 immediate and keeps track of bytes left and next offset
+func movZero(as int, width int64, nbytes int64, offset int64, regnum int16) (nleft int64, noff int64) {
+ p := Prog(as)
+ // TODO: use zero register on archs that support it.
+ p.From.Type = obj.TYPE_CONST
+ p.From.Offset = 0
+ p.To.Type = obj.TYPE_MEM
+ p.To.Reg = regnum
+ p.To.Offset = offset
+ offset += width
+ nleft = nbytes - width
+ return nleft, offset
+}
+
+var blockJump = [...]struct {
+ asm, invasm int
+}{
+ ssa.BlockAMD64EQ: {x86.AJEQ, x86.AJNE},
+ ssa.BlockAMD64NE: {x86.AJNE, x86.AJEQ},
+ ssa.BlockAMD64LT: {x86.AJLT, x86.AJGE},
+ ssa.BlockAMD64GE: {x86.AJGE, x86.AJLT},
+ ssa.BlockAMD64LE: {x86.AJLE, x86.AJGT},
+ ssa.BlockAMD64GT: {x86.AJGT, x86.AJLE},
+ ssa.BlockAMD64ULT: {x86.AJCS, x86.AJCC},
+ ssa.BlockAMD64UGE: {x86.AJCC, x86.AJCS},
+ ssa.BlockAMD64UGT: {x86.AJHI, x86.AJLS},
+ ssa.BlockAMD64ULE: {x86.AJLS, x86.AJHI},
+ ssa.BlockAMD64ORD: {x86.AJPC, x86.AJPS},
+ ssa.BlockAMD64NAN: {x86.AJPS, x86.AJPC},
+}
+
+type floatingEQNEJump struct {
+ jump, index int
+}
+
+var eqfJumps = [2][2]floatingEQNEJump{
+ {{x86.AJNE, 1}, {x86.AJPS, 1}}, // next == b.Succs[0]
+ {{x86.AJNE, 1}, {x86.AJPC, 0}}, // next == b.Succs[1]
+}
+var nefJumps = [2][2]floatingEQNEJump{
+ {{x86.AJNE, 0}, {x86.AJPC, 1}}, // next == b.Succs[0]
+ {{x86.AJNE, 0}, {x86.AJPS, 0}}, // next == b.Succs[1]
+}
+
+func oneFPJump(b *ssa.Block, jumps *floatingEQNEJump, likely ssa.BranchPrediction, branches []branch) []branch {
+ p := Prog(jumps.jump)
+ p.To.Type = obj.TYPE_BRANCH
+ to := jumps.index
+ branches = append(branches, branch{p, b.Succs[to]})
+ if to == 1 {
+ likely = -likely
+ }
+ // liblink reorders the instruction stream as it sees fit.
+ // Pass along what we know so liblink can make use of it.
+ // TODO: Once we've fully switched to SSA,
+ // make liblink leave our output alone.
+ switch likely {
+ case ssa.BranchUnlikely:
+ p.From.Type = obj.TYPE_CONST
+ p.From.Offset = 0
+ case ssa.BranchLikely:
+ p.From.Type = obj.TYPE_CONST
+ p.From.Offset = 1
+ }
+ return branches
+}
+
+func genFPJump(s *genState, b, next *ssa.Block, jumps *[2][2]floatingEQNEJump) {
+ likely := b.Likely
+ switch next {
+ case b.Succs[0]:
+ s.branches = oneFPJump(b, &jumps[0][0], likely, s.branches)
+ s.branches = oneFPJump(b, &jumps[0][1], likely, s.branches)
+ case b.Succs[1]:
+ s.branches = oneFPJump(b, &jumps[1][0], likely, s.branches)
+ s.branches = oneFPJump(b, &jumps[1][1], likely, s.branches)
+ default:
+ s.branches = oneFPJump(b, &jumps[1][0], likely, s.branches)
+ s.branches = oneFPJump(b, &jumps[1][1], likely, s.branches)
+ q := Prog(obj.AJMP)
+ q.To.Type = obj.TYPE_BRANCH
+ s.branches = append(s.branches, branch{q, b.Succs[1]})
+ }
+}
+
+func (s *genState) genBlock(b, next *ssa.Block) {
+ lineno = b.Line
+
+ // after a panic call, don't emit any branch code
+ if len(b.Values) > 0 {
+ switch b.Values[len(b.Values)-1].Op {
+ case ssa.OpAMD64LoweredPanicNilCheck,
+ ssa.OpAMD64LoweredPanicIndexCheck,
+ ssa.OpAMD64LoweredPanicSliceCheck:
+ return
+ }
+ }
+
+ switch b.Kind {
+ case ssa.BlockPlain:
+ if b.Succs[0] != next {
+ p := Prog(obj.AJMP)
+ p.To.Type = obj.TYPE_BRANCH
+ s.branches = append(s.branches, branch{p, b.Succs[0]})
+ }
+ case ssa.BlockExit:
+ case ssa.BlockRet:
- Fatal(msg, args...)
++ if hasdefer {
+ s.deferReturn()
+ }
+ Prog(obj.ARET)
+ case ssa.BlockCall:
+ if b.Succs[0] != next {
+ p := Prog(obj.AJMP)
+ p.To.Type = obj.TYPE_BRANCH
+ s.branches = append(s.branches, branch{p, b.Succs[0]})
+ }
+
+ case ssa.BlockAMD64EQF:
+ genFPJump(s, b, next, &eqfJumps)
+
+ case ssa.BlockAMD64NEF:
+ genFPJump(s, b, next, &nefJumps)
+
+ case ssa.BlockAMD64EQ, ssa.BlockAMD64NE,
+ ssa.BlockAMD64LT, ssa.BlockAMD64GE,
+ ssa.BlockAMD64LE, ssa.BlockAMD64GT,
+ ssa.BlockAMD64ULT, ssa.BlockAMD64UGT,
+ ssa.BlockAMD64ULE, ssa.BlockAMD64UGE:
+ jmp := blockJump[b.Kind]
+ likely := b.Likely
+ var p *obj.Prog
+ switch next {
+ case b.Succs[0]:
+ p = Prog(jmp.invasm)
+ likely *= -1
+ p.To.Type = obj.TYPE_BRANCH
+ s.branches = append(s.branches, branch{p, b.Succs[1]})
+ case b.Succs[1]:
+ p = Prog(jmp.asm)
+ p.To.Type = obj.TYPE_BRANCH
+ s.branches = append(s.branches, branch{p, b.Succs[0]})
+ default:
+ p = Prog(jmp.asm)
+ p.To.Type = obj.TYPE_BRANCH
+ s.branches = append(s.branches, branch{p, b.Succs[0]})
+ q := Prog(obj.AJMP)
+ q.To.Type = obj.TYPE_BRANCH
+ s.branches = append(s.branches, branch{q, b.Succs[1]})
+ }
+
+ // liblink reorders the instruction stream as it sees fit.
+ // Pass along what we know so liblink can make use of it.
+ // TODO: Once we've fully switched to SSA,
+ // make liblink leave our output alone.
+ switch likely {
+ case ssa.BranchUnlikely:
+ p.From.Type = obj.TYPE_CONST
+ p.From.Offset = 0
+ case ssa.BranchLikely:
+ p.From.Type = obj.TYPE_CONST
+ p.From.Offset = 1
+ }
+
+ default:
+ b.Unimplementedf("branch not implemented: %s. Control: %s", b.LongString(), b.Control.LongString())
+ }
+}
+
+func (s *genState) deferReturn() {
+ // Deferred calls will appear to be returning to
+ // the CALL deferreturn(SB) that we are about to emit.
+ // However, the stack trace code will show the line
+ // of the instruction byte before the return PC.
+ // To avoid that being an unrelated instruction,
+ // insert an actual hardware NOP that will have the right line number.
+ // This is different from obj.ANOP, which is a virtual no-op
+ // that doesn't make it into the instruction stream.
+ s.deferTarget = Pc
+ Thearch.Ginsnop()
+ p := Prog(obj.ACALL)
+ p.To.Type = obj.TYPE_MEM
+ p.To.Name = obj.NAME_EXTERN
+ p.To.Sym = Linksym(Deferreturn.Sym)
+}
+
+// addAux adds the offset in the aux fields (AuxInt and Aux) of v to a.
+func addAux(a *obj.Addr, v *ssa.Value) {
+ if a.Type != obj.TYPE_MEM {
+ v.Fatalf("bad addAux addr %s", a)
+ }
+ // add integer offset
+ a.Offset += v.AuxInt
+
+ // If no additional symbol offset, we're done.
+ if v.Aux == nil {
+ return
+ }
+ // Add symbol's offset from its base register.
+ switch sym := v.Aux.(type) {
+ case *ssa.ExternSymbol:
+ a.Name = obj.NAME_EXTERN
+ a.Sym = Linksym(sym.Sym.(*Sym))
+ case *ssa.ArgSymbol:
+ n := sym.Node.(*Node)
+ a.Name = obj.NAME_PARAM
+ a.Node = n
+ a.Sym = Linksym(n.Orig.Sym)
+ a.Offset += n.Xoffset // TODO: why do I have to add this here? I don't for auto variables.
+ case *ssa.AutoSymbol:
+ n := sym.Node.(*Node)
+ a.Name = obj.NAME_AUTO
+ a.Node = n
+ a.Sym = Linksym(n.Sym)
+ default:
+ v.Fatalf("aux in %s not implemented %#v", v, v.Aux)
+ }
+}
+
+// extendIndex extends v to a full pointer width.
+func (s *state) extendIndex(v *ssa.Value) *ssa.Value {
+ size := v.Type.Size()
+ if size == s.config.PtrSize {
+ return v
+ }
+ if size > s.config.PtrSize {
+ // TODO: truncate 64-bit indexes on 32-bit pointer archs. We'd need to test
+ // the high word and branch to out-of-bounds failure if it is not 0.
+ s.Unimplementedf("64->32 index truncation not implemented")
+ return v
+ }
+
+ // Extend value to the required size
+ var op ssa.Op
+ if v.Type.IsSigned() {
+ switch 10*size + s.config.PtrSize {
+ case 14:
+ op = ssa.OpSignExt8to32
+ case 18:
+ op = ssa.OpSignExt8to64
+ case 24:
+ op = ssa.OpSignExt16to32
+ case 28:
+ op = ssa.OpSignExt16to64
+ case 48:
+ op = ssa.OpSignExt32to64
+ default:
+ s.Fatalf("bad signed index extension %s", v.Type)
+ }
+ } else {
+ switch 10*size + s.config.PtrSize {
+ case 14:
+ op = ssa.OpZeroExt8to32
+ case 18:
+ op = ssa.OpZeroExt8to64
+ case 24:
+ op = ssa.OpZeroExt16to32
+ case 28:
+ op = ssa.OpZeroExt16to64
+ case 48:
+ op = ssa.OpZeroExt32to64
+ default:
+ s.Fatalf("bad unsigned index extension %s", v.Type)
+ }
+ }
+ return s.newValue1(op, Types[TUINTPTR], v)
+}
+
+// ssaRegToReg maps ssa register numbers to obj register numbers.
+var ssaRegToReg = [...]int16{
+ x86.REG_AX,
+ x86.REG_CX,
+ x86.REG_DX,
+ x86.REG_BX,
+ x86.REG_SP,
+ x86.REG_BP,
+ x86.REG_SI,
+ x86.REG_DI,
+ x86.REG_R8,
+ x86.REG_R9,
+ x86.REG_R10,
+ x86.REG_R11,
+ x86.REG_R12,
+ x86.REG_R13,
+ x86.REG_R14,
+ x86.REG_R15,
+ x86.REG_X0,
+ x86.REG_X1,
+ x86.REG_X2,
+ x86.REG_X3,
+ x86.REG_X4,
+ x86.REG_X5,
+ x86.REG_X6,
+ x86.REG_X7,
+ x86.REG_X8,
+ x86.REG_X9,
+ x86.REG_X10,
+ x86.REG_X11,
+ x86.REG_X12,
+ x86.REG_X13,
+ x86.REG_X14,
+ x86.REG_X15,
+ 0, // SB isn't a real register. We fill an Addr.Reg field with 0 in this case.
+ // TODO: arch-dependent
+}
+
+// regMoveAMD64 returns the register->register move opcode for the given width.
+// TODO: generalize for all architectures?
+func regMoveAMD64(width int64) int {
+ switch width {
+ case 1:
+ return x86.AMOVB
+ case 2:
+ return x86.AMOVW
+ case 4:
+ return x86.AMOVL
+ case 8:
+ return x86.AMOVQ
+ default:
+ panic("bad int register width")
+ }
+}
+
+func regMoveByTypeAMD64(t ssa.Type) int {
+ width := t.Size()
+ if t.IsFloat() {
+ switch width {
+ case 4:
+ return x86.AMOVSS
+ case 8:
+ return x86.AMOVSD
+ default:
+ panic("bad float register width")
+ }
+ } else {
+ switch width {
+ case 1:
+ return x86.AMOVB
+ case 2:
+ return x86.AMOVW
+ case 4:
+ return x86.AMOVL
+ case 8:
+ return x86.AMOVQ
+ default:
+ panic("bad int register width")
+ }
+ }
+
+ panic("bad register type")
+}
+
+// regnum returns the register (in cmd/internal/obj numbering) to
+// which v has been allocated. Panics if v is not assigned to a
+// register.
+// TODO: Make this panic again once it stops happening routinely.
+func regnum(v *ssa.Value) int16 {
+ reg := v.Block.Func.RegAlloc[v.ID]
+ if reg == nil {
+ v.Unimplementedf("nil regnum for value: %s\n%s\n", v.LongString(), v.Block.Func)
+ return 0
+ }
+ return ssaRegToReg[reg.(*ssa.Register).Num]
+}
+
+// autoVar returns a *Node representing the auto variable assigned to v.
+func autoVar(v *ssa.Value) *Node {
+ return v.Block.Func.RegAlloc[v.ID].(*ssa.LocalSlot).N.(*Node)
+}
+
+// ssaExport exports a bunch of compiler services for the ssa backend.
+type ssaExport struct {
+ log bool
+ unimplemented bool
+ mustImplement bool
+}
+
+func (s *ssaExport) TypeBool() ssa.Type { return Types[TBOOL] }
+func (s *ssaExport) TypeInt8() ssa.Type { return Types[TINT8] }
+func (s *ssaExport) TypeInt16() ssa.Type { return Types[TINT16] }
+func (s *ssaExport) TypeInt32() ssa.Type { return Types[TINT32] }
+func (s *ssaExport) TypeInt64() ssa.Type { return Types[TINT64] }
+func (s *ssaExport) TypeUInt8() ssa.Type { return Types[TUINT8] }
+func (s *ssaExport) TypeUInt16() ssa.Type { return Types[TUINT16] }
+func (s *ssaExport) TypeUInt32() ssa.Type { return Types[TUINT32] }
+func (s *ssaExport) TypeUInt64() ssa.Type { return Types[TUINT64] }
+func (s *ssaExport) TypeFloat32() ssa.Type { return Types[TFLOAT32] }
+func (s *ssaExport) TypeFloat64() ssa.Type { return Types[TFLOAT64] }
+func (s *ssaExport) TypeInt() ssa.Type { return Types[TINT] }
+func (s *ssaExport) TypeUintptr() ssa.Type { return Types[TUINTPTR] }
+func (s *ssaExport) TypeString() ssa.Type { return Types[TSTRING] }
+func (s *ssaExport) TypeBytePtr() ssa.Type { return Ptrto(Types[TUINT8]) }
+
+// StringData returns a symbol (a *Sym wrapped in an interface) which
+// is the data component of a global string constant containing s.
+func (*ssaExport) StringData(s string) interface{} {
+ // TODO: is idealstring correct? It might not matter...
+ _, data := stringsym(s)
+ return &ssa.ExternSymbol{Typ: idealstring, Sym: data}
+}
+
+func (e *ssaExport) Auto(t ssa.Type) fmt.Stringer {
+ n := temp(t.(*Type)) // Note: adds new auto to Curfn.Func.Dcl list
+ e.mustImplement = true // This modifies the input to SSA, so we want to make sure we succeed from here!
+ return n
+}
+
+// Log logs a message from the compiler.
+func (e *ssaExport) Logf(msg string, args ...interface{}) {
+ // If e was marked as unimplemented, anything could happen. Ignore.
+ if e.log && !e.unimplemented {
+ fmt.Printf(msg, args...)
+ }
+}
+
+// Fatal reports a compiler error and exits.
+func (e *ssaExport) Fatalf(msg string, args ...interface{}) {
+ // If e was marked as unimplemented, anything could happen. Ignore.
+ if !e.unimplemented {
- Fatal(msg, args...)
++ Fatalf(msg, args...)
+ }
+}
+
+// Unimplemented reports that the function cannot be compiled.
+// It will be removed once SSA work is complete.
+func (e *ssaExport) Unimplementedf(msg string, args ...interface{}) {
+ if e.mustImplement {
++ Fatalf(msg, args...)
+ }
+ const alwaysLog = false // enable to calculate top unimplemented features
+ if !e.unimplemented && (e.log || alwaysLog) {
+ // first implementation failure, print explanation
+ fmt.Printf("SSA unimplemented: "+msg+"\n", args...)
+ }
+ e.unimplemented = true
+}