From: Jake Ciolek <jakub@ciolek.dev>
Date: Sat, 9 Oct 2021 15:57:06 +0000 (+0200)
Subject: cmd/compile: mark NOT as an op that doesn't clobber flags on i386/AMD64
X-Git-Tag: go1.18beta1~961
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=ba2c9fef035da3ef93e0eb0dbf4d583663829139;p=gostls13.git

cmd/compile: mark NOT as an op that doesn't clobber flags on i386/AMD64

NOT does not affect any FLAGS register values on i386/AMD64 so we do not
need to mark it as an Op that clobbers them.

Change-Id: I6d99cad49cfa2568b01e58190256582b18fb3b7b
Reviewed-on: https://go-review.googlesource.com/c/go/+/354831
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
---

diff --git a/src/cmd/compile/internal/ssa/gen/386Ops.go b/src/cmd/compile/internal/ssa/gen/386Ops.go
index 3512d60865..a6da7a5fce 100644
--- a/src/cmd/compile/internal/ssa/gen/386Ops.go
+++ b/src/cmd/compile/internal/ssa/gen/386Ops.go
@@ -298,7 +298,7 @@ func init() {
 		// unary ops
 		{name: "NEGL", argLength: 1, reg: gp11, asm: "NEGL", resultInArg0: true, clobberFlags: true}, // -arg0
 
-		{name: "NOTL", argLength: 1, reg: gp11, asm: "NOTL", resultInArg0: true, clobberFlags: true}, // ^arg0
+		{name: "NOTL", argLength: 1, reg: gp11, asm: "NOTL", resultInArg0: true}, // ^arg0
 
 		{name: "BSFL", argLength: 1, reg: gp11, asm: "BSFL", clobberFlags: true}, // arg0 # of low-order zeroes ; undef if zero
 		{name: "BSFW", argLength: 1, reg: gp11, asm: "BSFW", clobberFlags: true}, // arg0 # of low-order zeroes ; undef if zero
diff --git a/src/cmd/compile/internal/ssa/gen/AMD64Ops.go b/src/cmd/compile/internal/ssa/gen/AMD64Ops.go
index 1887772736..731454c761 100644
--- a/src/cmd/compile/internal/ssa/gen/AMD64Ops.go
+++ b/src/cmd/compile/internal/ssa/gen/AMD64Ops.go
@@ -513,8 +513,8 @@ func init() {
 		{name: "NEGQ", argLength: 1, reg: gp11, asm: "NEGQ", resultInArg0: true, clobberFlags: true}, // -arg0
 		{name: "NEGL", argLength: 1, reg: gp11, asm: "NEGL", resultInArg0: true, clobberFlags: true}, // -arg0
 
-		{name: "NOTQ", argLength: 1, reg: gp11, asm: "NOTQ", resultInArg0: true, clobberFlags: true}, // ^arg0
-		{name: "NOTL", argLength: 1, reg: gp11, asm: "NOTL", resultInArg0: true, clobberFlags: true}, // ^arg0
+		{name: "NOTQ", argLength: 1, reg: gp11, asm: "NOTQ", resultInArg0: true}, // ^arg0
+		{name: "NOTL", argLength: 1, reg: gp11, asm: "NOTL", resultInArg0: true}, // ^arg0
 
 		// BS{F,R}Q returns a tuple [result, flags]
 		// result is undefined if the input is zero.
diff --git a/src/cmd/compile/internal/ssa/opGen.go b/src/cmd/compile/internal/ssa/opGen.go
index 09006c8c85..640e517fe7 100644
--- a/src/cmd/compile/internal/ssa/opGen.go
+++ b/src/cmd/compile/internal/ssa/opGen.go
@@ -4733,7 +4733,6 @@ var opcodeTable = [...]opInfo{
 		name:         "NOTL",
 		argLen:       1,
 		resultInArg0: true,
-		clobberFlags: true,
 		asm:          x86.ANOTL,
 		reg: regInfo{
 			inputs: []inputInfo{
@@ -10777,7 +10776,6 @@ var opcodeTable = [...]opInfo{
 		name:         "NOTQ",
 		argLen:       1,
 		resultInArg0: true,
-		clobberFlags: true,
 		asm:          x86.ANOTQ,
 		reg: regInfo{
 			inputs: []inputInfo{
@@ -10792,7 +10790,6 @@ var opcodeTable = [...]opInfo{
 		name:         "NOTL",
 		argLen:       1,
 		resultInArg0: true,
-		clobberFlags: true,
 		asm:          x86.ANOTL,
 		reg: regInfo{
 			inputs: []inputInfo{