Subzero: Simplify the icmp i64 lowering.

src/IceTargetLoweringX8632.cpp

@@ -2710,8 +2710,6 @@ void TargetX8632::lowerIcmp(const InstIcmp *Inst) {
   }
 
   // a=icmp cond, b, c ==> cmp b,c; a=1; br cond,L1; FakeUse(a); a=0; L1:
-  Constant *Zero = Ctx->getConstantZero(IceType_i32);
-  Constant *One = Ctx->getConstantInt32(1);
   if (Src0->getType() == IceType_i64) {
     InstIcmp::ICond Condition = Inst->getCondition();
     size_t Index = static_cast<size_t>(Condition);
@@ -2720,28 +2718,21 @@ void TargetX8632::lowerIcmp(const InstIcmp *Inst) {
     Operand *Src0HiRM = legalize(hiOperand(Src0), Legal_Reg | Legal_Mem);
     Operand *Src1LoRI = legalize(loOperand(Src1), Legal_Reg | Legal_Imm);
     Operand *Src1HiRI = legalize(hiOperand(Src1), Legal_Reg | Legal_Imm);
-    if (Condition == InstIcmp::Eq || Condition == InstIcmp::Ne) {
-      InstX8632Label *Label = InstX8632Label::create(Func, this);
-      _mov(Dest, (Condition == InstIcmp::Eq ? Zero : One));
-      _cmp(Src0LoRM, Src1LoRI);
-      _br(CondX86::Br_ne, Label);
-      _cmp(Src0HiRM, Src1HiRI);
-      _br(CondX86::Br_ne, Label);
-      _mov_nonkillable(Dest, (Condition == InstIcmp::Eq ? One : Zero));
-      Context.insert(Label);
-    } else {
-      InstX8632Label *LabelFalse = InstX8632Label::create(Func, this);
-      InstX8632Label *LabelTrue = InstX8632Label::create(Func, this);
-      _mov(Dest, One);
-      _cmp(Src0HiRM, Src1HiRI);
+    Constant *Zero = Ctx->getConstantZero(IceType_i32);
+    Constant *One = Ctx->getConstantInt32(1);
+    InstX8632Label *LabelFalse = InstX8632Label::create(Func, this);
+    InstX8632Label *LabelTrue = InstX8632Label::create(Func, this);
+    _mov(Dest, One);
+    _cmp(Src0HiRM, Src1HiRI);
+    if (TableIcmp64[Index].C1 != CondX86::Br_None)
       _br(TableIcmp64[Index].C1, LabelTrue);
+    if (TableIcmp64[Index].C2 != CondX86::Br_None)
       _br(TableIcmp64[Index].C2, LabelFalse);
-      _cmp(Src0LoRM, Src1LoRI);
-      _br(TableIcmp64[Index].C3, LabelTrue);
-      Context.insert(LabelFalse);
-      _mov_nonkillable(Dest, Zero);
-      Context.insert(LabelTrue);
-    }
+    _cmp(Src0LoRM, Src1LoRI);
+    _br(TableIcmp64[Index].C3, LabelTrue);
+    Context.insert(LabelFalse);
+    _mov_nonkillable(Dest, Zero);
+    Context.insert(LabelTrue);
     return;
   }
 

src/IceTargetLoweringX8632.def

@@ -38,8 +38,8 @@
 
 #define ICMPX8632_TABLE                     \
   /* val, C_32,  C1_64,   C2_64,   C3_64 */ \
-  X(Eq,   Br_e,  Br_None, Br_None, Br_None) \
-  X(Ne,   Br_ne, Br_None, Br_None, Br_None) \
+  X(Eq,   Br_e,  Br_None, Br_ne,   Br_e)    \
+  X(Ne,   Br_ne, Br_ne,   Br_None, Br_ne)   \
   X(Ugt,  Br_a,  Br_a,    Br_b,    Br_a)    \
   X(Uge,  Br_ae, Br_a,    Br_b,    Br_ae)   \
   X(Ult,  Br_b,  Br_b,    Br_a,    Br_b)    \

tests_lit/llvm2ice_tests/64bit.pnacl.ll

@@ -732,18 +732,18 @@ if.end3:                                          ; preds = %if.then2, %if.end
 }
 ; CHECK-LABEL: icmpEq64
 ; CHECK: jne
-; CHECK: jne
+; CHECK: je
 ; CHECK: call
 ; CHECK: jne
-; CHECK: jne
+; CHECK: je
 ; CHECK: call
 ;
 ; OPTM1-LABEL: icmpEq64
 ; OPTM1: jne
-; OPTM1: jne
+; OPTM1: je
 ; OPTM1: call
 ; OPTM1: jne
-; OPTM1: jne
+; OPTM1: je
 ; OPTM1: call
 
 declare void @func()
@@ -952,11 +952,11 @@ entry:
 }
 ; CHECK-LABEL: icmpEq64Bool
 ; CHECK: jne
-; CHECK: jne
+; CHECK: je
 ;
 ; OPTM1-LABEL: icmpEq64Bool
 ; OPTM1: jne
-; OPTM1: jne
+; OPTM1: je
 
 define internal i32 @icmpNe64Bool(i64 %a, i64 %b) {
 entry: