1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
|
; RUN: opt -S -passes=gvn < %s | FileCheck %s
; 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 ptr @calloc(i64 1, i64 4)
; This load is trivially constant zero
%2 = load i32, ptr %1, align 4
ret i32 %2
; CHECK-LABEL: @test1(
; CHECK-NOT: %2 = load i32, ptr %1, align 4
; CHECK: ret i32 0
; CHECK_NO_LIBCALLS-LABEL: @test1(
; CHECK_NO_LIBCALLS: load
; CHECK_NO_LIBCALLS: ret i32 %
}
define i32 @as_invoke(i1 %c) personality ptr undef {
bb3:
%mem = invoke noalias ptr @calloc(i64 1, i64 4)
to label %bb4 unwind label %bb1
bb1:
%lp = landingpad { ptr, i32 } cleanup
ret i32 0
bb4:
; This load is trivially constant zero
%res = load i32, ptr %mem, align 4
ret i32 %res
; CHECK-LABEL: @as_invoke(
; CHECK-NOT: %3 = load i32, ptr %2, align 4
; CHECK: ret i32 0
; CHECK_NO_LIBCALLS-LABEL: @as_invoke(
; CHECK_NO_LIBCALLS: load
; CHECK_NO_LIBCALLS: ret i32 %
}
declare noalias ptr @calloc(i64, i64) allockind("alloc,zeroed") allocsize(0,1)
|
