[llvm-commits] [llvm] r74699 - in /llvm/trunk: lib/Analysis/ValueTracking.cpp test/Transforms/InstCombine/2009-07-02-MaskedIntVector.ll

[Chris Lattner]

Author: lattner
Date: Thu Jul  2 11:04:08 2009
New Revision: 74699

URL: http://llvm.org/viewvc/llvm-project?rev=74699&view=rev
Log:
do not try to analyze bitcasts from i64 to <2 x i32> in ComputedMaskedBits.  While
we could do this, doing so requires adjusting the demanded mask and the code isn't 
doing that yet.  This fixes PR4495

Added:
    llvm/trunk/test/Transforms/InstCombine/2009-07-02-MaskedIntVector.ll
Modified:
    llvm/trunk/lib/Analysis/ValueTracking.cpp

Modified: llvm/trunk/lib/Analysis/ValueTracking.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ValueTracking.cpp?rev=74699&r1=74698&r2=74699&view=diff

==============================================================================
--- llvm/trunk/lib/Analysis/ValueTracking.cpp (original)
+++ llvm/trunk/lib/Analysis/ValueTracking.cpp Thu Jul  2 11:04:08 2009
@@ -249,7 +249,10 @@
   }
   case Instruction::BitCast: {
     const Type *SrcTy = I->getOperand(0)->getType();
-    if (SrcTy->isInteger() || isa<PointerType>(SrcTy)) {
+    if ((SrcTy->isInteger() || isa<PointerType>(SrcTy)) &&
+        // TODO: For now, not handling conversions like:
+        // (bitcast i64 %x to <2 x i32>)
+        !isa<VectorType>(I->getType())) {
       ComputeMaskedBits(I->getOperand(0), Mask, KnownZero, KnownOne, TD,
                         Depth+1);
       return;

Added: llvm/trunk/test/Transforms/InstCombine/2009-07-02-MaskedIntVector.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/2009-07-02-MaskedIntVector.ll?rev=74699&view=auto

==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/2009-07-02-MaskedIntVector.ll (added)
+++ llvm/trunk/test/Transforms/InstCombine/2009-07-02-MaskedIntVector.ll Thu Jul  2 11:04:08 2009
@@ -0,0 +1,15 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis
+; PR4495
+
+define i32 @test(i64 %test) {
+entry:
+	%0 = bitcast <4 x i32> undef to <16 x i8>		; <<16 x i8>> [#uses=1]
+	%t12 = shufflevector <16 x i8> %0, <16 x i8> zeroinitializer, <16 x i32> <i32 0, i32 16, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0>		; <<16 x i8>> [#uses=1]
+	%t11 = bitcast <16 x i8> %t12 to <2 x i64>		; <<2 x i64>> [#uses=1]
+	%t9 = extractelement <2 x i64> %t11, i32 0		; <i64> [#uses=1]
+	%t10 = bitcast i64 %t9 to <2 x i32>		; <<2 x i32>> [#uses=1]
+	%t7 = bitcast i64 %test to <2 x i32>		; <<2 x i32>> [#uses=1]
+	%t6 = xor <2 x i32> %t10, %t7		; <<2 x i32>> [#uses=1]
+	%t1 = extractelement <2 x i32> %t6, i32 0		; <i32> [#uses=1]
+	ret i32 %t1
+}