[llvm-commits] [llvm] r173093 - in /llvm/trunk: lib/Transforms/InstCombine/InstCombineAddSub.cpp test/Transforms/InstCombine/mul.ll test/Transforms/InstCombine/sext.ll test/Transforms/InstCombine/zext-bool-add-sub.ll

[Paul Redmond]

Author: predmond
Date: Mon Jan 21 15:57:20 2013
New Revision: 173093

URL: http://llvm.org/viewvc/llvm-project?rev=173093&view=rev
Log:
Transform (sub 0, (zext bool to A)) to (sext bool to A) and
(sub 0, (sext bool to A)) to (zext bool to A).

Patch by Muhammad Ahmad
Reviewed by Duncan Sands

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombineAddSub.cpp
    llvm/trunk/test/Transforms/InstCombine/mul.ll
    llvm/trunk/test/Transforms/InstCombine/sext.ll
    llvm/trunk/test/Transforms/InstCombine/zext-bool-add-sub.ll

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineAddSub.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineAddSub.cpp?rev=173093&r1=173092&r2=173093&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineAddSub.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineAddSub.cpp Mon Jan 21 15:57:20 2013
@@ -1250,6 +1250,16 @@
 
     if (SimplifyDemandedInstructionBits(I))
       return &I;
+
+    // Fold (sub 0, (zext bool to B)) --> (sext bool to B)
+    if (C->isZero() && match(Op1, m_ZExt(m_Value(X))))
+      if (X->getType()->isIntegerTy(1))
+        return CastInst::CreateSExtOrBitCast(X, Op1->getType());
+
+    // Fold (sub 0, (sext bool to B)) --> (zext bool to B)
+    if (C->isZero() && match(Op1, m_SExt(m_Value(X))))
+      if (X->getType()->isIntegerTy(1))
+        return CastInst::CreateZExtOrBitCast(X, Op1->getType());
   }
 
 

Modified: llvm/trunk/test/Transforms/InstCombine/mul.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/mul.ll?rev=173093&r1=173092&r2=173093&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/mul.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/mul.ll Mon Jan 21 15:57:20 2013
@@ -138,8 +138,7 @@
         ; e = b & (a >> 31)
         %e = mul i32 %d, %b             ; <i32> [#uses=1]
         ret i32 %e
-; CHECK: [[TEST16:%.*]] = zext i1 %c to i32
-; CHECK-NEXT: %1 = sub i32 0, [[TEST16]]
+; CHECK: [[TEST16:%.*]] = sext i1 %c to i32
 ; CHECK-NEXT: %e = and i32 %1, %b
 ; CHECK-NEXT: ret i32 %e
 }

Modified: llvm/trunk/test/Transforms/InstCombine/sext.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/sext.ll?rev=173093&r1=173092&r2=173093&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/sext.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/sext.ll Mon Jan 21 15:57:20 2013
@@ -184,3 +184,12 @@
 ; CHECK-NEXT: %ext = sext i16 %sext to i32
 ; CHECK-NEXT: ret i32 %ext
 }
+
+define i32 @test17(i1 %x) nounwind {
+  %c1 = sext i1 %x to i32
+  %c2 = sub i32 0, %c1
+  ret i32 %c2
+; CHECK: @test17
+; CHECK-NEXT: [[TEST17:%.*]] = zext i1 %x to i32
+; CHECK-NEXT: ret i32 [[TEST17]]
+}

Modified: llvm/trunk/test/Transforms/InstCombine/zext-bool-add-sub.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/zext-bool-add-sub.ll?rev=173093&r1=173092&r2=173093&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/zext-bool-add-sub.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/zext-bool-add-sub.ll Mon Jan 21 15:57:20 2013
@@ -4,9 +4,9 @@
 define i32 @a(i1 zeroext %x, i1 zeroext %y) {
 entry:
 ; CHECK: @a
-; CHECK: [[TMP1:%.*]] = zext i1 %y to i32
+; CHECK: [[TMP1:%.*]] = sext i1 %y to i32
 ; CHECK: [[TMP2:%.*]] = select i1 %x, i32 2, i32 1
-; CHECK-NEXT: sub i32 [[TMP2]], [[TMP1]]
+; CHECK-NEXT: add i32 [[TMP2]], [[TMP1]]
   %conv = zext i1 %x to i32
   %conv3 = zext i1 %y to i32
   %conv3.neg = sub i32 0, %conv3