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| ; RUN: opt -instcombine -S < %s | FileCheck %s
; #include <stdlib.h>
; #include <stdio.h>
;
; int foo1(int N) {
; char Big[20];
; char Small[10];
; char *Ptr = N ? Big + 10 : Small;
; return __builtin_object_size(Ptr, 0);
; }
;
; void foo() {
; size_t ret;
; ret = foo1(0);
; printf("\n %d", ret);
; }
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@.str = private unnamed_addr constant [5 x i8] c"\0A %d\00", align 1
define i32 @foo1(i32 %N) {
entry:
%Big = alloca [20 x i8], align 16
%Small = alloca [10 x i8], align 1
%0 = getelementptr inbounds [20 x i8], [20 x i8]* %Big, i64 0, i64 0
call void @llvm.lifetime.start.p0i8(i64 20, i8* %0)
%1 = getelementptr inbounds [10 x i8], [10 x i8]* %Small, i64 0, i64 0
call void @llvm.lifetime.start.p0i8(i64 10, i8* %1)
%tobool = icmp ne i32 %N, 0
%add.ptr = getelementptr inbounds [20 x i8], [20 x i8]* %Big, i64 0, i64 10
%cond = select i1 %tobool, i8* %add.ptr, i8* %1
%2 = call i64 @llvm.objectsize.i64.p0i8(i8* %cond, i1 false)
%conv = trunc i64 %2 to i32
call void @llvm.lifetime.end.p0i8(i64 10, i8* %1)
call void @llvm.lifetime.end.p0i8(i64 20, i8* %0)
ret i32 %conv
; CHECK: ret i32 10
}
declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture)
declare i64 @llvm.objectsize.i64.p0i8(i8*, i1)
declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture)
define void @foo() {
entry:
%call = tail call i32 @foo1(i32 0)
%conv = sext i32 %call to i64
%call1 = tail call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0), i64 %conv)
ret void
}
declare i32 @printf(i8* nocapture readonly, ...)
|