; RUN: opt -S -instcombine < %s | FileCheck %s 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-n8:16:32" target triple = "i386-apple-darwin10.0.0" ; CHECK: define void @fu1 define void @fu1(i32 %parm) nounwind ssp { %1 = alloca i32, align 4 ; CHECK: alloca double* %ptr = alloca double*, align 4 store i32 %parm, i32* %1, align 4 store double* null, double** %ptr, align 4 %2 = load i32* %1, align 4 %3 = icmp ne i32 %2, 0 br i1 %3, label %4, label %10 ; <label>:4 ; preds = %0 %5 = load i32* %1, align 4 %6 = mul nsw i32 %5, 8 ; With "nsw", the alloca and its bitcast can be fused: %7 = add nsw i32 %6, 2048 ; CHECK: alloca double %8 = alloca i8, i32 %7 %9 = bitcast i8* %8 to double* ; CHECK-NEXT: store double* store double* %9, double** %ptr, align 4 br label %10 ; <label>:10 ; preds = %4, %0 %11 = load double** %ptr, align 4 call void @bar(double* %11) ; CHECK: ret ret void } declare void @bar(double*) ; CHECK: define void @fu2 define void @fu2(i32 %parm) nounwind ssp { %1 = alloca i32, align 4 %ptr = alloca double*, align 4 store i32 %parm, i32* %1, align 4 store double* null, double** %ptr, align 4 %2 = load i32* %1, align 4 %3 = icmp ne i32 %2, 0 br i1 %3, label %4, label %10 ; <label>:4 ; preds = %0 %5 = load i32* %1, align 4 %6 = mul nsw i32 %5, 8 ; Without "nsw", the alloca and its bitcast cannot be fused: %7 = add i32 %6, 2048 ; CHECK: alloca i8 %8 = alloca i8, i32 %7 ; CHECK-NEXT: bitcast i8* %9 = bitcast i8* %8 to double* store double* %9, double** %ptr, align 4 br label %10 ; <label>:10 ; preds = %4, %0 %11 = load double** %ptr, align 4 call void @bar(double* %11) ret void }