[llvm] r365324 - [Float2Int] Add support for unary FNeg to Float2Int

[Cameron McInally via llvm-commits]

Author: mcinally
Date: Mon Jul  8 07:46:07 2019
New Revision: 365324

URL: http://llvm.org/viewvc/llvm-project?rev=365324&view=rev
Log:
[Float2Int] Add support for unary FNeg to Float2Int

Differential Revision: https://reviews.llvm.org/D63941

Modified:
    llvm/trunk/lib/Transforms/Scalar/Float2Int.cpp
    llvm/trunk/test/Transforms/Float2Int/basic.ll

Modified: llvm/trunk/lib/Transforms/Scalar/Float2Int.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/Float2Int.cpp?rev=365324&r1=365323&r2=365324&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/Float2Int.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/Float2Int.cpp Mon Jul  8 07:46:07 2019
@@ -200,6 +200,7 @@ void Float2IntPass::walkBackwards(const
       continue;
     }
 
+    case Instruction::FNeg:
     case Instruction::FAdd:
     case Instruction::FSub:
     case Instruction::FMul:
@@ -240,6 +241,15 @@ void Float2IntPass::walkForwards() {
     case Instruction::SIToFP:
       llvm_unreachable("Should have been handled in walkForwards!");
 
+    case Instruction::FNeg:
+      Op = [](ArrayRef<ConstantRange> Ops) {
+        assert(Ops.size() == 1 && "FNeg is a unary operator!");
+        unsigned Size = Ops[0].getBitWidth();
+        auto Zero = ConstantRange(APInt::getNullValue(Size));
+        return Zero.sub(Ops[0]);
+      };
+      break;
+
     case Instruction::FAdd:
     case Instruction::FSub:
     case Instruction::FMul:
@@ -466,6 +476,10 @@ Value *Float2IntPass::convert(Instructio
     NewV = IRB.CreateSExtOrTrunc(NewOperands[0], ToTy);
     break;
 
+  case Instruction::FNeg:
+    NewV = IRB.CreateNeg(NewOperands[0], I->getName());
+    break;
+
   case Instruction::FAdd:
   case Instruction::FSub:
   case Instruction::FMul:

Modified: llvm/trunk/test/Transforms/Float2Int/basic.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/Float2Int/basic.ll?rev=365324&r1=365323&r2=365324&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/Float2Int/basic.ll (original)
+++ llvm/trunk/test/Transforms/Float2Int/basic.ll Mon Jul  8 07:46:07 2019
@@ -80,12 +80,11 @@ define i32 @simple5(i8 %a, i8 %b) {
 }
 
 ; CHECK-LABEL: @simple6
-; CHECK:  %1 = uitofp i8 %a to float
-; CHECK:  %2 = uitofp i8 %b to float
-; CHECK:  %3 = fneg float %1
-; CHECK:  %4 = fmul float %3, %2
-; CHECK:  %5 = fptoui float %4 to i32
-; CHECK:  ret i32 %5
+; CHECK:  %1 = zext i8 %a to i32
+; CHECK:  %2 = zext i8 %b to i32
+; CHECK:  %3 = sub i32 0, %1
+; CHECK:  %4 = mul i32 %3, %2
+; CHECK:  ret i32 %4
 define i32 @simple6(i8 %a, i8 %b) {
   %1 = uitofp i8 %a to float
   %2 = uitofp i8 %b to float
@@ -145,6 +144,18 @@ define i32 @simple_negative(i8 %call) {
   ret i32 %conv3
 }
 
+; CHECK-LABEL: @simple_fneg
+; CHECK:  %1 = zext i8 %a to i32
+; CHECK:  %2 = sub i32 0, %1
+; CHECK:  %3 = trunc i32 %2 to i16
+; CHECK:  ret i16 %3
+define i16 @simple_fneg(i8 %a) {
+  %1 = uitofp i8 %a to float
+  %2 = fneg fast float %1
+  %3 = fptoui float %2 to i16
+  ret i16 %3
+}
+
 ;
 ; Negative tests
 ;