cmd/compile: remove support for old-style bounds check calls

This CL rips out the support for old-style assembly stubs.

We need to keep the Go stubs for wasm support.

Change-Id: I23d6d9f2f06be1ded8d22b3e0ef04ff6e252a587
Reviewed-on: https://go-review.googlesource.com/c/go/+/682402
Reviewed-by: Austin Clements <austin@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

diff --git a/src/cmd/compile/internal/ssa/op.go b/src/cmd/compile/internal/ssa/op.go
index d5c7394a2678155cf36dd13a99bcadf5a80cf51a..e8bd5d9acf591795b71f1690d88fb66df97a41f8 100644 (file)
--- a/src/cmd/compile/internal/ssa/op.go
+++ b/src/cmd/compile/internal/ssa/op.go
@@ -485,53 +485,6 @@ const (
        BoundsKindCount
 )
 
-// boundsABI determines which register arguments a bounds check call should use. For an [a:b:c] slice, we do:
-//
-//     CMPQ c, cap
-//     JA   fail1
-//     CMPQ b, c
-//     JA   fail2
-//     CMPQ a, b
-//     JA   fail3
-//
-// fail1: CALL panicSlice3Acap (c, cap)
-// fail2: CALL panicSlice3B (b, c)
-// fail3: CALL panicSlice3C (a, b)
-//
-// When we register allocate that code, we want the same register to be used for
-// the first arg of panicSlice3Acap and the second arg to panicSlice3B. That way,
-// initializing that register once will satisfy both calls.
-// That desire ends up dividing the set of bounds check calls into 3 sets. This function
-// determines which set to use for a given panic call.
-// The first arg for set 0 should be the second arg for set 1.
-// The first arg for set 1 should be the second arg for set 2.
-func boundsABI(b int64) int {
-       switch BoundsKind(b) {
-       case BoundsSlice3Alen,
-               BoundsSlice3AlenU,
-               BoundsSlice3Acap,
-               BoundsSlice3AcapU,
-               BoundsConvert:
-               return 0
-       case BoundsSliceAlen,
-               BoundsSliceAlenU,
-               BoundsSliceAcap,
-               BoundsSliceAcapU,
-               BoundsSlice3B,
-               BoundsSlice3BU:
-               return 1
-       case BoundsIndex,
-               BoundsIndexU,
-               BoundsSliceB,
-               BoundsSliceBU,
-               BoundsSlice3C,
-               BoundsSlice3CU:
-               return 2
-       default:
-               panic("bad BoundsKind")
-       }
-}
-
 // Returns the bounds error code needed by the runtime, and
 // whether the x field is signed.
 func (b BoundsKind) Code() (rtabi.BoundsErrorCode, bool) {

diff --git a/src/cmd/compile/internal/ssagen/ssa.go b/src/cmd/compile/internal/ssagen/ssa.go
index bce94d35f94841f4a09b32c148e3331030651e5b..72928f267bf36030ef37f5ed62032aab878fd47d 100644 (file)
--- a/src/cmd/compile/internal/ssagen/ssa.go
+++ b/src/cmd/compile/internal/ssagen/ssa.go
@@ -184,42 +184,6 @@ func InitConfig() {
                BoundsCheckFunc[ssa.BoundsSlice3C] = typecheck.LookupRuntimeFunc("goPanicSlice3C")
                BoundsCheckFunc[ssa.BoundsSlice3CU] = typecheck.LookupRuntimeFunc("goPanicSlice3CU")
                BoundsCheckFunc[ssa.BoundsConvert] = typecheck.LookupRuntimeFunc("goPanicSliceConvert")
-       } else {
-               BoundsCheckFunc[ssa.BoundsIndex] = typecheck.LookupRuntimeFunc("panicIndex")
-               BoundsCheckFunc[ssa.BoundsIndexU] = typecheck.LookupRuntimeFunc("panicIndexU")
-               BoundsCheckFunc[ssa.BoundsSliceAlen] = typecheck.LookupRuntimeFunc("panicSliceAlen")
-               BoundsCheckFunc[ssa.BoundsSliceAlenU] = typecheck.LookupRuntimeFunc("panicSliceAlenU")
-               BoundsCheckFunc[ssa.BoundsSliceAcap] = typecheck.LookupRuntimeFunc("panicSliceAcap")
-               BoundsCheckFunc[ssa.BoundsSliceAcapU] = typecheck.LookupRuntimeFunc("panicSliceAcapU")
-               BoundsCheckFunc[ssa.BoundsSliceB] = typecheck.LookupRuntimeFunc("panicSliceB")
-               BoundsCheckFunc[ssa.BoundsSliceBU] = typecheck.LookupRuntimeFunc("panicSliceBU")
-               BoundsCheckFunc[ssa.BoundsSlice3Alen] = typecheck.LookupRuntimeFunc("panicSlice3Alen")
-               BoundsCheckFunc[ssa.BoundsSlice3AlenU] = typecheck.LookupRuntimeFunc("panicSlice3AlenU")
-               BoundsCheckFunc[ssa.BoundsSlice3Acap] = typecheck.LookupRuntimeFunc("panicSlice3Acap")
-               BoundsCheckFunc[ssa.BoundsSlice3AcapU] = typecheck.LookupRuntimeFunc("panicSlice3AcapU")
-               BoundsCheckFunc[ssa.BoundsSlice3B] = typecheck.LookupRuntimeFunc("panicSlice3B")
-               BoundsCheckFunc[ssa.BoundsSlice3BU] = typecheck.LookupRuntimeFunc("panicSlice3BU")
-               BoundsCheckFunc[ssa.BoundsSlice3C] = typecheck.LookupRuntimeFunc("panicSlice3C")
-               BoundsCheckFunc[ssa.BoundsSlice3CU] = typecheck.LookupRuntimeFunc("panicSlice3CU")
-               BoundsCheckFunc[ssa.BoundsConvert] = typecheck.LookupRuntimeFunc("panicSliceConvert")
-       }
-       if Arch.LinkArch.PtrSize == 4 {
-               ExtendCheckFunc[ssa.BoundsIndex] = typecheck.LookupRuntimeVar("panicExtendIndex")
-               ExtendCheckFunc[ssa.BoundsIndexU] = typecheck.LookupRuntimeVar("panicExtendIndexU")
-               ExtendCheckFunc[ssa.BoundsSliceAlen] = typecheck.LookupRuntimeVar("panicExtendSliceAlen")
-               ExtendCheckFunc[ssa.BoundsSliceAlenU] = typecheck.LookupRuntimeVar("panicExtendSliceAlenU")
-               ExtendCheckFunc[ssa.BoundsSliceAcap] = typecheck.LookupRuntimeVar("panicExtendSliceAcap")
-               ExtendCheckFunc[ssa.BoundsSliceAcapU] = typecheck.LookupRuntimeVar("panicExtendSliceAcapU")
-               ExtendCheckFunc[ssa.BoundsSliceB] = typecheck.LookupRuntimeVar("panicExtendSliceB")
-               ExtendCheckFunc[ssa.BoundsSliceBU] = typecheck.LookupRuntimeVar("panicExtendSliceBU")
-               ExtendCheckFunc[ssa.BoundsSlice3Alen] = typecheck.LookupRuntimeVar("panicExtendSlice3Alen")
-               ExtendCheckFunc[ssa.BoundsSlice3AlenU] = typecheck.LookupRuntimeVar("panicExtendSlice3AlenU")
-               ExtendCheckFunc[ssa.BoundsSlice3Acap] = typecheck.LookupRuntimeVar("panicExtendSlice3Acap")
-               ExtendCheckFunc[ssa.BoundsSlice3AcapU] = typecheck.LookupRuntimeVar("panicExtendSlice3AcapU")
-               ExtendCheckFunc[ssa.BoundsSlice3B] = typecheck.LookupRuntimeVar("panicExtendSlice3B")
-               ExtendCheckFunc[ssa.BoundsSlice3BU] = typecheck.LookupRuntimeVar("panicExtendSlice3BU")
-               ExtendCheckFunc[ssa.BoundsSlice3C] = typecheck.LookupRuntimeVar("panicExtendSlice3C")
-               ExtendCheckFunc[ssa.BoundsSlice3CU] = typecheck.LookupRuntimeVar("panicExtendSlice3CU")
        }
 
        // Wasm (all asm funcs with special ABIs)
@@ -7758,7 +7722,4 @@ func SpillSlotAddr(spill ssa.Spill, baseReg int16, extraOffset int64) obj.Addr {
        }
 }
 
-var (
-       BoundsCheckFunc [ssa.BoundsKindCount]*obj.LSym
-       ExtendCheckFunc [ssa.BoundsKindCount]*obj.LSym
-)
+var BoundsCheckFunc [ssa.BoundsKindCount]*obj.LSym

diff --git a/src/runtime/panic.go b/src/runtime/panic.go
index 8f9ab4dd47345b95deedb244611bde53e542fe50..8c91c9435abd18d81a644289480e3ec2c83e48bc 100644 (file)
--- a/src/runtime/panic.go
+++ b/src/runtime/panic.go
@@ -103,9 +103,8 @@ func panicCheck2(err string) {
 // these (they always look like they're called from the runtime).
 // Hence, for these, we just check for clearly bad runtime conditions.
 //
-// The panic{Index,Slice} functions are implemented in assembly and tail call
-// to the goPanic{Index,Slice} functions below. This is done so we can use
-// a space-minimal register calling convention.
+// The goPanic{Index,Slice} functions are only used by wasm. All the other architectures
+// use panic{Bounds,Extend} in assembly, which then call to panicBounds{64,32,32X}.
 
 // failures in the comparisons for s[x], 0 <= x < y (y == len(s))
 //
@@ -205,28 +204,10 @@ func goPanicSliceConvert(x int, y int) {
        panic(boundsError{x: int64(x), signed: true, y: y, code: abi.BoundsConvert})
 }
 
-// Implemented in assembly, as they take arguments in registers.
-// Declared here to mark them as ABIInternal.
-func panicIndex(x int, y int)
-func panicIndexU(x uint, y int)
-func panicSliceAlen(x int, y int)
-func panicSliceAlenU(x uint, y int)
-func panicSliceAcap(x int, y int)
-func panicSliceAcapU(x uint, y int)
-func panicSliceB(x int, y int)
-func panicSliceBU(x uint, y int)
-func panicSlice3Alen(x int, y int)
-func panicSlice3AlenU(x uint, y int)
-func panicSlice3Acap(x int, y int)
-func panicSlice3AcapU(x uint, y int)
-func panicSlice3B(x int, y int)
-func panicSlice3BU(x uint, y int)
-func panicSlice3C(x int, y int)
-func panicSlice3CU(x uint, y int)
-func panicSliceConvert(x int, y int)
-
+// Implemented in assembly. Declared here to mark them as ABIInternal.
 func panicBounds() // in asm_GOARCH.s files, called from generated code
 func panicExtend() // in asm_GOARCH.s files, called from generated code (on 32-bit archs)
+
 func panicBounds64(pc uintptr, regs *[16]int64) { // called from panicBounds on 64-bit archs
        f := findfunc(pc)
        v := pcdatavalue(f, abi.PCDATA_PanicBounds, pc-1)