[llvm-commits] [llvm] r46539 - in /llvm/trunk: lib/Transforms/Scalar/ScalarReplAggregates.cpp test/Transforms/ScalarRepl/2008-01-29-PromoteBug.ll

[Chris Lattner]

Author: lattner
Date: Tue Jan 29 18:39:15 2008
New Revision: 46539

URL: http://llvm.org/viewvc/llvm-project?rev=46539&view=rev
Log:
Fix a bug where scalarrepl would discard offset if type would match.
In practice this can only happen on code with already undefined behavior, 
but this is still a good thing to handle correctly.

Added:
    llvm/trunk/test/Transforms/ScalarRepl/2008-01-29-PromoteBug.ll
Modified:
    llvm/trunk/lib/Transforms/Scalar/ScalarReplAggregates.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/ScalarReplAggregates.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/ScalarReplAggregates.cpp?rev=46539&r1=46538&r2=46539&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/ScalarReplAggregates.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/ScalarReplAggregates.cpp Tue Jan 29 18:39:15 2008
@@ -1078,7 +1078,7 @@
     if (LoadInst *LI = dyn_cast<LoadInst>(User)) {
       // The load is a bit extract from NewAI shifted right by Offset bits.
       Value *NV = new LoadInst(NewAI, LI->getName(), LI);
-      if (NV->getType() == LI->getType()) {
+      if (NV->getType() == LI->getType() && Offset == 0) {
         // We win, no conversion needed.
       } else if (const VectorType *PTy = dyn_cast<VectorType>(NV->getType())) {
         // If the result alloca is a vector type, this is either an element
@@ -1232,7 +1232,7 @@
       SI->eraseFromParent();
       
     } else if (BitCastInst *CI = dyn_cast<BitCastInst>(User)) {
-       ConvertUsesToScalar(CI, NewAI, Offset);
+      ConvertUsesToScalar(CI, NewAI, Offset);
       CI->eraseFromParent();
     } else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(User)) {
       const PointerType *AggPtrTy = 

Added: llvm/trunk/test/Transforms/ScalarRepl/2008-01-29-PromoteBug.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/ScalarRepl/2008-01-29-PromoteBug.ll?rev=46539&view=auto

==============================================================================
--- llvm/trunk/test/Transforms/ScalarRepl/2008-01-29-PromoteBug.ll (added)
+++ llvm/trunk/test/Transforms/ScalarRepl/2008-01-29-PromoteBug.ll Tue Jan 29 18:39:15 2008
@@ -0,0 +1,21 @@
+; RUN: llvm-as < %s | opt -scalarrepl -instcombine | llvm-dis | grep {ret i8 17}
+; rdar://5707076
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+target triple = "i386-apple-darwin9.1.0"
+	%struct.T = type <{ i8, [3 x i8] }>
+
+define i8 @f() {
+entry:
+	%s = alloca [1 x %struct.T], align 4		; <[1 x %struct.T]*> [#uses=2]
+	%T3 = bitcast [1 x %struct.T]* %s to i32*
+	store i32 -61184, i32* %T3
+
+	%tmp16 = getelementptr [1 x %struct.T]* %s, i32 0, i32 0		; <%struct.T*> [#uses=1]
+	%tmp17 = getelementptr %struct.T* %tmp16, i32 0, i32 1		; <[3 x i8]*> [#uses=1]
+	%tmp1718 = bitcast [3 x i8]* %tmp17 to i32*		; <i32*> [#uses=1]
+	%tmp19 = load i32* %tmp1718, align 4		; <i32> [#uses=1]
+	%mask = and i32 %tmp19, 16777215		; <i32> [#uses=2]
+	%mask2324 = trunc i32 %mask to i8		; <i8> [#uses=1]
+	ret i8 %mask2324
+}
+