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; RUN: opt -opaque-pointers=0 -S -passes=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-LABEL: define void @fu1(
define void @fu1(i32 %parm) #0 {
bb:
%i = alloca i32, align 4
; CHECK: alloca double*
%ptr = alloca double*, align 4
store i32 %parm, i32* %i, align 4
store double* null, double** %ptr, align 4
%i1 = load i32, i32* %i, align 4
%i2 = icmp ne i32 %i1, 0
br i1 %i2, label %bb3, label %bb9
bb3: ; preds = %bb
%i4 = load i32, i32* %i, align 4
%i5 = shl nuw i32 %i4, 3
; With "nuw", the alloca and its bitcast can be fused:
%i6 = add nuw i32 %i5, 2048
; CHECK: alloca double
%i7 = alloca i8, i32 %i6, align 1
%i8 = bitcast i8* %i7 to double*
; CHECK-NEXT: store double*
store double* %i8, double** %ptr, align 4
br label %bb9
bb9: ; preds = %bb3, %bb
%i10 = load double*, double** %ptr, align 4
call void @bar(double* %i10)
ret void
}
declare void @bar(double*)
; CHECK-LABEL: define void @fu2(
define void @fu2(i32 %parm) #0 {
bb:
%i = alloca i32, align 4
%ptr = alloca double*, align 4
store i32 %parm, i32* %i, align 4
store double* null, double** %ptr, align 4
%i1 = load i32, i32* %i, align 4
%i2 = icmp ne i32 %i1, 0
br i1 %i2, label %bb3, label %bb9
bb3: ; preds = %bb
%i4 = load i32, i32* %i, align 4
%i5 = mul nuw i32 %i4, 8
; Without "nuw", the alloca and its bitcast cannot be fused:
%i6 = add i32 %i5, 2048
; CHECK: alloca i8
%i7 = alloca i8, i32 %i6, align 1
; CHECK-NEXT: bitcast double**
; CHECK-NEXT: store i8*
%i8 = bitcast i8* %i7 to double*
store double* %i8, double** %ptr, align 4
br label %bb9
bb9: ; preds = %bb3, %bb
%i10 = load double*, double** %ptr, align 4
call void @bar(double* %i10)
ret void
}
attributes #0 = { nounwind ssp }
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