26 lines
837 B
LLVM
26 lines
837 B
LLVM
|
; RUN: opt -S -basic-aa -gvn < %s | FileCheck %s
|
||
|
; RUN: opt -S -basic-aa -gvn -disable-simplify-libcalls < %s | FileCheck %s -check-prefix=CHECK_NO_LIBCALLS
|
||
|
; Check that loads from calloc are recognized as being zero.
|
||
|
|
||
|
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
|
||
|
|
||
|
; Function Attrs: nounwind uwtable
|
||
|
define i32 @test1() {
|
||
|
%1 = tail call noalias i8* @calloc(i64 1, i64 4)
|
||
|
%2 = bitcast i8* %1 to i32*
|
||
|
; This load is trivially constant zero
|
||
|
%3 = load i32, i32* %2, align 4
|
||
|
ret i32 %3
|
||
|
|
||
|
; CHECK-LABEL: @test1(
|
||
|
; CHECK-NOT: %3 = load i32, i32* %2, align 4
|
||
|
; CHECK: ret i32 0
|
||
|
|
||
|
; CHECK_NO_LIBCALLS-LABEL: @test1(
|
||
|
; CHECK_NO_LIBCALLS: load
|
||
|
; CHECK_NO_LIBCALLS: ret i32 %
|
||
|
|
||
|
}
|
||
|
|
||
|
declare noalias i8* @calloc(i64, i64)
|