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
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
; RUN: llc < %s -mtriple=arm-pc-windows-msvc | FileCheck %s
; Control Flow Guard is currently only available on Windows
; Test that Control Flow Guard checks are correctly added when required.
declare i32 @target_func()
; Test that Control Flow Guard checks are not added on calls with the "guard_nocf" attribute.
define i32 @func_guard_nocf() #0 {
entry:
%func_ptr = alloca i32 ()*, align 8
store i32 ()* @target_func, i32 ()** %func_ptr, align 8
%0 = load i32 ()*, i32 ()** %func_ptr, align 8
%1 = call arm_aapcs_vfpcc i32 %0() #1
ret i32 %1
; CHECK-LABEL: func_guard_nocf
; CHECK: movw r0, :lower16:target_func
; CHECK: movt r0, :upper16:target_func
; CHECK-NOT: __guard_check_icall_fptr
; CHECK: blx r0
}
attributes #0 = { "target-cpu"="cortex-a9" "target-features"="+armv7-a,+dsp,+fp16,+neon,+strict-align,+thumb-mode,+vfp3"}
attributes #1 = { "guard_nocf" }
; Test that Control Flow Guard checks are added even at -O0.
define i32 @func_optnone_cf() #2 {
entry:
%func_ptr = alloca i32 ()*, align 8
store i32 ()* @target_func, i32 ()** %func_ptr, align 8
%0 = load i32 ()*, i32 ()** %func_ptr, align 8
%1 = call i32 %0()
ret i32 %1
; The call to __guard_check_icall_fptr should come immediately before the call to the target function.
; CHECK-LABEL: func_optnone_cf
; CHECK: movw r0, :lower16:target_func
; CHECK: movt r0, :upper16:target_func
; CHECK: str r0, [sp]
; CHECK: ldr r4, [sp]
; CHECK: movw r0, :lower16:__guard_check_icall_fptr
; CHECK: movt r0, :upper16:__guard_check_icall_fptr
; CHECK: ldr r1, [r0]
; CHECK: mov r0, r4
; CHECK: blx r1
; CHECK-NEXT: blx r4
}
attributes #2 = { noinline optnone "target-cpu"="cortex-a9" "target-features"="+armv7-a,+dsp,+fp16,+neon,+strict-align,+thumb-mode,+vfp3"}
; Test that Control Flow Guard checks are correctly added in optimized code (common case).
define i32 @func_cf() #0 {
entry:
%func_ptr = alloca i32 ()*, align 8
store i32 ()* @target_func, i32 ()** %func_ptr, align 8
%0 = load i32 ()*, i32 ()** %func_ptr, align 8
%1 = call i32 %0()
ret i32 %1
; The call to __guard_check_icall_fptr should come immediately before the call to the target function.
; CHECK-LABEL: func_cf
; CHECK: movw r0, :lower16:__guard_check_icall_fptr
; CHECK: movt r0, :upper16:__guard_check_icall_fptr
; CHECK: ldr r1, [r0]
; CHECK: movw r4, :lower16:target_func
; CHECK: movt r4, :upper16:target_func
; CHECK: mov r0, r4
; CHECK: blx r1
; CHECK-NEXT: blx r4
}
; Test that Control Flow Guard checks are correctly added on invoke instructions.
define i32 @func_cf_invoke() #0 personality i8* bitcast (void ()* @h to i8*) {
entry:
%0 = alloca i32, align 4
%func_ptr = alloca i32 ()*, align 8
store i32 ()* @target_func, i32 ()** %func_ptr, align 8
%1 = load i32 ()*, i32 ()** %func_ptr, align 8
%2 = invoke i32 %1()
to label %invoke.cont unwind label %lpad
invoke.cont: ; preds = %entry
ret i32 %2
lpad: ; preds = %entry
%tmp = landingpad { i8*, i32 }
catch i8* null
ret i32 -1
; The call to __guard_check_icall_fptr should come immediately before the call to the target function.
; CHECK-LABEL: func_cf_invoke
; CHECK: movw r0, :lower16:__guard_check_icall_fptr
; CHECK: movt r0, :upper16:__guard_check_icall_fptr
; CHECK: ldr r1, [r0]
; CHECK: movw r4, :lower16:target_func
; CHECK: movt r4, :upper16:target_func
; CHECK: mov r0, r4
; CHECK: blx r1
; CHECK-NEXT: $Mtmp0:
; CHECK-NEXT: blx r4
; CHECK: @ %common.ret
; CHECK: @ %lpad
}
declare void @h()
; Test that longjmp targets have public labels and are included in the .gljmp section.
%struct._SETJMP_FLOAT128 = type { [2 x i64] }
@buf1 = internal global [16 x %struct._SETJMP_FLOAT128] zeroinitializer, align 16
define i32 @func_cf_setjmp() #0 {
%1 = alloca i32, align 4
%2 = alloca i32, align 4
store i32 0, i32* %1, align 4
store i32 -1, i32* %2, align 4
%3 = call i8* @llvm.frameaddress(i32 0)
%4 = call i32 @_setjmp(i8* bitcast ([16 x %struct._SETJMP_FLOAT128]* @buf1 to i8*), i8* %3) #3
; CHECK-LABEL: func_cf_setjmp
; CHECK: bl _setjmp
; CHECK-NEXT: $cfgsj_func_cf_setjmp0:
%5 = call i8* @llvm.frameaddress(i32 0)
%6 = call i32 @_setjmp(i8* bitcast ([16 x %struct._SETJMP_FLOAT128]* @buf1 to i8*), i8* %5) #3
; CHECK: bl _setjmp
; CHECK-NEXT: $cfgsj_func_cf_setjmp1:
store i32 1, i32* %2, align 4
%7 = load i32, i32* %2, align 4
ret i32 %7
; CHECK: .section .gljmp$y,"dr"
; CHECK-NEXT: .symidx $cfgsj_func_cf_setjmp0
; CHECK-NEXT: .symidx $cfgsj_func_cf_setjmp1
}
declare i8* @llvm.frameaddress(i32)
; Function Attrs: returns_twice
declare dso_local i32 @_setjmp(i8*, i8*) #3
attributes #3 = { returns_twice }
!llvm.module.flags = !{!0}
!0 = !{i32 2, !"cfguard", i32 2}
|
