diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 06a67493750..a7e817a8e65 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -7533,11 +7533,13 @@ static unsigned GetKnownAlignment(Value *V, TargetData *TD) { const Type *BasePtrTy = GEPI->getOperand(0)->getType(); const PointerType *PtrTy = cast(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(GEPTy); - return TD->getABITypeAlignment(GEPPtrTy->getElementType()); + Align = std::min(Align, (unsigned) + TD->getABITypeAlignment(GEPPtrTy->getElementType())); + return Align; } return 0; } diff --git a/test/Transforms/InstCombine/known_align.ll b/test/Transforms/InstCombine/known_align.ll new file mode 100644 index 00000000000..a6e340902df --- /dev/null +++ b/test/Transforms/InstCombine/known_align.ll @@ -0,0 +1,27 @@ +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep {align 1} +; END. + + %struct.p = type <{ i8, i32 }> +@t = global %struct.p <{ i8 1, i32 10 }> ; <%struct.p*> [#uses=1] +@u = weak global %struct.p zeroinitializer ; <%struct.p*> [#uses=1] + +define i32 @main() { +entry: + %retval = alloca i32, align 4 ; [#uses=2] + %tmp = alloca i32, align 4 ; [#uses=2] + %tmp1 = alloca i32, align 4 ; [#uses=3] + %"alloca point" = bitcast i32 0 to i32 ; [#uses=0] + %tmp3 = load i32* getelementptr (%struct.p* @t, i32 0, i32 1), align 1 ; [#uses=1] + store i32 %tmp3, i32* %tmp1, align 4 + %tmp5 = load i32* %tmp1, align 4 ; [#uses=1] + store i32 %tmp5, i32* getelementptr (%struct.p* @u, i32 0, i32 1), align 1 + %tmp6 = load i32* %tmp1, align 4 ; [#uses=1] + store i32 %tmp6, i32* %tmp, align 4 + %tmp7 = load i32* %tmp, align 4 ; [#uses=1] + store i32 %tmp7, i32* %retval, align 4 + br label %return + +return: ; preds = %entry + %retval8 = load i32* %retval ; [#uses=1] + ret i32 %retval8 +}