cmd/compile: remove nil check for Zero/Move on 386, AMD64, S390X

Fixes #18003.

Change-Id: Iadcc5c424c64badecfb5fdbd4dbd9197df56182c
Reviewed-on: https://go-review.googlesource.com/33421
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

diff --git a/src/cmd/compile/internal/ssa/gen/386Ops.go b/src/cmd/compile/internal/ssa/gen/386Ops.go
index 1d150db6644e3b78e66efa60b1f5694a28e93cf2..bcbf2cbed3c802c535fd8824105426e296c9ea7e 100644 (file)
--- a/src/cmd/compile/internal/ssa/gen/386Ops.go
+++ b/src/cmd/compile/internal/ssa/gen/386Ops.go
@@ -373,6 +373,7 @@ func init() {
                                clobbers: buildReg("DI CX"),
                                // Note: CX is only clobbered when dynamic linking.
                        },
+                       faultOnNilArg0: true,
                },
 
                // arg0 = address of memory to zero
@@ -387,6 +388,7 @@ func init() {
                                inputs:   []regMask{buildReg("DI"), buildReg("CX"), buildReg("AX")},
                                clobbers: buildReg("DI CX"),
                        },
+                       faultOnNilArg0: true,
                },
 
                {name: "CALLstatic", argLength: 1, reg: regInfo{clobbers: callerSave}, aux: "SymOff", clobberFlags: true, call: true},                                             // call static function aux.(*gc.Sym).  arg0=mem, auxint=argsize, returns mem
@@ -408,7 +410,9 @@ func init() {
                                inputs:   []regMask{buildReg("DI"), buildReg("SI")},
                                clobbers: buildReg("DI SI CX"), // uses CX as a temporary
                        },
-                       clobberFlags: true,
+                       clobberFlags:   true,
+                       faultOnNilArg0: true,
+                       faultOnNilArg1: true,
                },
 
                // arg0 = destination pointer
@@ -423,6 +427,8 @@ func init() {
                                inputs:   []regMask{buildReg("DI"), buildReg("SI"), buildReg("CX")},
                                clobbers: buildReg("DI SI CX"),
                        },
+                       faultOnNilArg0: true,
+                       faultOnNilArg1: true,
                },
 
                // (InvertFlags (CMPL a b)) == (CMPL b a)

diff --git a/src/cmd/compile/internal/ssa/gen/AMD64Ops.go b/src/cmd/compile/internal/ssa/gen/AMD64Ops.go
index b42ede4ad00ffb2bd2d6216a3d1062c63fa4968c..69f3f769556d2b0c93b1daa5f2d97a94abaefb88 100644 (file)
--- a/src/cmd/compile/internal/ssa/gen/AMD64Ops.go
+++ b/src/cmd/compile/internal/ssa/gen/AMD64Ops.go
@@ -421,7 +421,8 @@ func init() {
                                inputs:   []regMask{buildReg("DI"), buildReg("X0")},
                                clobbers: buildReg("DI"),
                        },
-                       clobberFlags: true,
+                       clobberFlags:   true,
+                       faultOnNilArg0: true,
                },
                {name: "MOVOconst", reg: regInfo{nil, 0, []regMask{fp}}, typ: "Int128", aux: "Int128", rematerializeable: true},
 
@@ -437,6 +438,7 @@ func init() {
                                inputs:   []regMask{buildReg("DI"), buildReg("CX"), buildReg("AX")},
                                clobbers: buildReg("DI CX"),
                        },
+                       faultOnNilArg0: true,
                },
 
                {name: "CALLstatic", argLength: 1, reg: regInfo{clobbers: callerSave}, aux: "SymOff", clobberFlags: true, call: true},                                             // call static function aux.(*gc.Sym).  arg0=mem, auxint=argsize, returns mem
@@ -458,7 +460,9 @@ func init() {
                                inputs:   []regMask{buildReg("DI"), buildReg("SI")},
                                clobbers: buildReg("DI SI X0"), // uses X0 as a temporary
                        },
-                       clobberFlags: true,
+                       clobberFlags:   true,
+                       faultOnNilArg0: true,
+                       faultOnNilArg1: true,
                },
 
                // arg0 = destination pointer
@@ -473,6 +477,8 @@ func init() {
                                inputs:   []regMask{buildReg("DI"), buildReg("SI"), buildReg("CX")},
                                clobbers: buildReg("DI SI CX"),
                        },
+                       faultOnNilArg0: true,
+                       faultOnNilArg1: true,
                },
 
                // (InvertFlags (CMPQ a b)) == (CMPQ b a)

diff --git a/src/cmd/compile/internal/ssa/gen/S390XOps.go b/src/cmd/compile/internal/ssa/gen/S390XOps.go
index 7a25c267846b05a20887ddc6726de85d4f5860a3..99c3a4da4a921460e89eaa747e823877fde0685f 100644 (file)
--- a/src/cmd/compile/internal/ssa/gen/S390XOps.go
+++ b/src/cmd/compile/internal/ssa/gen/S390XOps.go
@@ -568,8 +568,10 @@ func init() {
                                inputs:   []regMask{buildReg("R1"), buildReg("R2"), gpsp},
                                clobbers: buildReg("R1 R2"),
                        },
-                       clobberFlags: true,
-                       typ:          "Mem",
+                       clobberFlags:   true,
+                       typ:            "Mem",
+                       faultOnNilArg0: true,
+                       faultOnNilArg1: true,
                },
 
                // large clear
@@ -592,8 +594,9 @@ func init() {
                                inputs:   []regMask{buildReg("R1"), gpsp},
                                clobbers: buildReg("R1"),
                        },
-                       clobberFlags: true,
-                       typ:          "Mem",
+                       clobberFlags:   true,
+                       typ:            "Mem",
+                       faultOnNilArg0: true,
                },
        }
 

diff --git a/src/cmd/compile/internal/ssa/opGen.go b/src/cmd/compile/internal/ssa/opGen.go
index 510fcfea1028c75234e0fd7157541ec652d344f9..f4cc1c0b81b706ce0ae6cd826a6cab9d47cc4d56 100644 (file)
--- a/src/cmd/compile/internal/ssa/opGen.go
+++ b/src/cmd/compile/internal/ssa/opGen.go
@@ -4071,9 +4071,10 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:    "DUFFZERO",
-               auxType: auxInt64,
-               argLen:  3,
+               name:           "DUFFZERO",
+               auxType:        auxInt64,
+               argLen:         3,
+               faultOnNilArg0: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 128}, // DI
@@ -4083,8 +4084,9 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:   "REPSTOSL",
-               argLen: 4,
+               name:           "REPSTOSL",
+               argLen:         4,
+               faultOnNilArg0: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 128}, // DI
@@ -4152,10 +4154,12 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:         "DUFFCOPY",
-               auxType:      auxInt64,
-               argLen:       3,
-               clobberFlags: true,
+               name:           "DUFFCOPY",
+               auxType:        auxInt64,
+               argLen:         3,
+               clobberFlags:   true,
+               faultOnNilArg0: true,
+               faultOnNilArg1: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 128}, // DI
@@ -4165,8 +4169,10 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:   "REPMOVSL",
-               argLen: 4,
+               name:           "REPMOVSL",
+               argLen:         4,
+               faultOnNilArg0: true,
+               faultOnNilArg1: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 128}, // DI
@@ -7062,10 +7068,11 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:         "DUFFZERO",
-               auxType:      auxInt64,
-               argLen:       3,
-               clobberFlags: true,
+               name:           "DUFFZERO",
+               auxType:        auxInt64,
+               argLen:         3,
+               clobberFlags:   true,
+               faultOnNilArg0: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 128},   // DI
@@ -7086,8 +7093,9 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:   "REPSTOSQ",
-               argLen: 4,
+               name:           "REPSTOSQ",
+               argLen:         4,
+               faultOnNilArg0: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 128}, // DI
@@ -7155,10 +7163,12 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:         "DUFFCOPY",
-               auxType:      auxInt64,
-               argLen:       3,
-               clobberFlags: true,
+               name:           "DUFFCOPY",
+               auxType:        auxInt64,
+               argLen:         3,
+               clobberFlags:   true,
+               faultOnNilArg0: true,
+               faultOnNilArg1: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 128}, // DI
@@ -7168,8 +7178,10 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:   "REPMOVSQ",
-               argLen: 4,
+               name:           "REPMOVSQ",
+               argLen:         4,
+               faultOnNilArg0: true,
+               faultOnNilArg1: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 128}, // DI
@@ -19714,10 +19726,12 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:         "LoweredMove",
-               auxType:      auxInt64,
-               argLen:       4,
-               clobberFlags: true,
+               name:           "LoweredMove",
+               auxType:        auxInt64,
+               argLen:         4,
+               clobberFlags:   true,
+               faultOnNilArg0: true,
+               faultOnNilArg1: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 2},     // R1
@@ -19728,10 +19742,11 @@ var opcodeTable = [...]opInfo{
                },
        },
        {
-               name:         "LoweredZero",
-               auxType:      auxInt64,
-               argLen:       3,
-               clobberFlags: true,
+               name:           "LoweredZero",
+               auxType:        auxInt64,
+               argLen:         3,
+               clobberFlags:   true,
+               faultOnNilArg0: true,
                reg: regInfo{
                        inputs: []inputInfo{
                                {0, 2},     // R1

diff --git a/test/nilptr3.go b/test/nilptr3.go
index c681cba50c4cf1ce93c0c1fa278cd8c4a933d316..7af226b5f4db38933579f6412143bb9aeaa67ffd 100644 (file)
--- a/test/nilptr3.go
+++ b/test/nilptr3.go
@@ -254,3 +254,8 @@ func f7() (*Struct, float64) {
        p := &t.Y    // ERROR "removed nil check"
        return t, *p // ERROR "removed nil check"
 }
+
+// make sure to remove nil check for memory move (issue #18003)
+func f8(t *[8]int) [8]int {
+       return *t // ERROR "removed nil check"
+}