[llvm-commits] [llvm] r40649 - in /llvm/trunk: lib/Transforms/Scalar/InstructionCombining.cpp test/Transforms/InstCombine/known_align.ll

[Lauro Ramos Venancio]

Author: laurov
Date: Tue Jul 31 15:13:21 2007
New Revision: 40649

URL: http://llvm.org/viewvc/llvm-project?rev=40649&view=rev
Log:
Fix a bug in GetKnownAlignment of packed structs.


Added:
    llvm/trunk/test/Transforms/InstCombine/known_align.ll
Modified:
    llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp?rev=40649&r1=40648&r2=40649&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp Tue Jul 31 15:13:21 2007
@@ -7533,11 +7533,13 @@
 
     const Type *BasePtrTy = GEPI->getOperand(0)->getType();
     const PointerType *PtrTy = cast<PointerType>(BasePtrTy);
-    if (TD->getABITypeAlignment(PtrTy->getElementType())
-        <= BaseAlignment) {
+    unsigned Align = TD->getABITypeAlignment(PtrTy->getElementType());
+    if (Align <= BaseAlignment) {
       const Type *GEPTy = GEPI->getType();
       const PointerType *GEPPtrTy = cast<PointerType>(GEPTy);
-      return TD->getABITypeAlignment(GEPPtrTy->getElementType());
+      Align = std::min(Align, (unsigned)
+                       TD->getABITypeAlignment(GEPPtrTy->getElementType()));
+      return Align;
     }
     return 0;
   }

Added: llvm/trunk/test/Transforms/InstCombine/known_align.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/known_align.ll?rev=40649&view=auto

==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/known_align.ll (added)
+++ llvm/trunk/test/Transforms/InstCombine/known_align.ll Tue Jul 31 15:13:21 2007
@@ -0,0 +1,27 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep {align 1}
+; END.
+
+	%struct.p = type <{ i8, i32 }>
+ at t = global %struct.p <{ i8 1, i32 10 }>		; <%struct.p*> [#uses=1]
+ at u = weak global %struct.p zeroinitializer		; <%struct.p*> [#uses=1]
+
+define i32 @main() {
+entry:
+	%retval = alloca i32, align 4		; <i32*> [#uses=2]
+	%tmp = alloca i32, align 4		; <i32*> [#uses=2]
+	%tmp1 = alloca i32, align 4		; <i32*> [#uses=3]
+	%"alloca point" = bitcast i32 0 to i32		; <i32> [#uses=0]
+	%tmp3 = load i32* getelementptr (%struct.p* @t, i32 0, i32 1), align 1		; <i32> [#uses=1]
+	store i32 %tmp3, i32* %tmp1, align 4
+	%tmp5 = load i32* %tmp1, align 4		; <i32> [#uses=1]
+	store i32 %tmp5, i32* getelementptr (%struct.p* @u, i32 0, i32 1), align 1
+	%tmp6 = load i32* %tmp1, align 4		; <i32> [#uses=1]
+	store i32 %tmp6, i32* %tmp, align 4
+	%tmp7 = load i32* %tmp, align 4		; <i32> [#uses=1]
+	store i32 %tmp7, i32* %retval, align 4
+	br label %return
+
+return:		; preds = %entry
+	%retval8 = load i32* %retval		; <i32> [#uses=1]
+	ret i32 %retval8
+}