[release-branch.go1.18] cmd/compile: fix boolean comparison on PPC64

Following CL 421457, for PPC64.

Should fix PPC64 builds.

Updates #52788.
Updates #53397.

Change-Id: I193ac31cfba18b4f907dd2523b51368251fd6fad
Reviewed-on: https://go-review.googlesource.com/c/go/+/405116
TryBot-Result: Gopher Robot <[email protected]>
Run-TryBot: Cherry Mui <[email protected]>
Reviewed-by: David Chase <[email protected]>
Reviewed-on: https://go-review.googlesource.com/c/go/+/421459
Reviewed-by: Cherry Mui <[email protected]>
Run-TryBot: Dmitri Shuralyov <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>

Author: cherrymui

src/cmd/compile/internal/ssa/gen/PPC64.rules

@@ -445,19 +445,19 @@
 (If (FGreaterThan cc) yes no) => (FGT cc yes no)
 (If (FGreaterEqual cc) yes no) => (FGE cc yes no)
 
-(If cond yes no) => (NE (CMPWconst [0] cond) yes no)
+(If cond yes no) => (NE (CMPWconst [0] (ANDconst <typ.UInt32> [1] cond)) yes no)
 
 // Absorb boolean tests into block
-(NE (CMPWconst [0] (Equal cc)) yes no) => (EQ cc yes no)
-(NE (CMPWconst [0] (NotEqual cc)) yes no) => (NE cc yes no)
-(NE (CMPWconst [0] (LessThan cc)) yes no) => (LT cc yes no)
-(NE (CMPWconst [0] (LessEqual cc)) yes no) => (LE cc yes no)
-(NE (CMPWconst [0] (GreaterThan cc)) yes no) => (GT cc yes no)
-(NE (CMPWconst [0] (GreaterEqual cc)) yes no) => (GE cc yes no)
-(NE (CMPWconst [0] (FLessThan cc)) yes no) => (FLT cc yes no)
-(NE (CMPWconst [0] (FLessEqual cc)) yes no) => (FLE cc yes no)
-(NE (CMPWconst [0] (FGreaterThan cc)) yes no) => (FGT cc yes no)
-(NE (CMPWconst [0] (FGreaterEqual cc)) yes no) => (FGE cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (Equal cc))) yes no) => (EQ cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (NotEqual cc))) yes no) => (NE cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (LessThan cc))) yes no) => (LT cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (LessEqual cc))) yes no) => (LE cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (GreaterThan cc))) yes no) => (GT cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (GreaterEqual cc))) yes no) => (GE cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (FLessThan cc))) yes no) => (FLT cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (FLessEqual cc))) yes no) => (FLE cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (FGreaterThan cc))) yes no) => (FGT cc yes no)
+(NE (CMPWconst [0] (ANDconst [1] (FGreaterEqual cc))) yes no) => (FGE cc yes no)
 
 // Elide compares of bit tests // TODO need to make both CC and result of ANDCC available.
 (EQ (CMPconst [0] (ANDconst [c] x)) yes no) => (EQ (ANDCCconst [c] x) yes no)

src/cmd/compile/internal/ssa/rewritePPC64.go

@@ -102,7 +102,7 @@ var ppcNeed = []string{
 var ppcGnuNeed = []string{
 	"mflr",
 	"lbz",
-	"cmpw",
+	"beq",
 }
 
 func mustHaveDisasm(t *testing.T) {