1; RUN: llc < %s -mtriple=arm-pc-windows-msvc | FileCheck %s 2; Control Flow Guard is currently only available on Windows 3 4; Test that Control Flow Guard checks are correctly added when required. 5 6 7declare i32 @target_func() 8 9 10; Test that Control Flow Guard checks are not added on calls with the "guard_nocf" attribute. 11define i32 @func_guard_nocf() #0 { 12entry: 13 %func_ptr = alloca i32 ()*, align 8 14 store i32 ()* @target_func, i32 ()** %func_ptr, align 8 15 %0 = load i32 ()*, i32 ()** %func_ptr, align 8 16 %1 = call arm_aapcs_vfpcc i32 %0() #1 17 ret i32 %1 18 19 ; CHECK-LABEL: func_guard_nocf 20 ; CHECK: movw r0, :lower16:target_func 21 ; CHECK: movt r0, :upper16:target_func 22 ; CHECK-NOT: __guard_check_icall_fptr 23 ; CHECK: blx r0 24} 25attributes #0 = { "target-cpu"="cortex-a9" "target-features"="+armv7-a,+dsp,+fp16,+neon,+strict-align,+thumb-mode,+vfp3"} 26attributes #1 = { "guard_nocf" } 27 28 29; Test that Control Flow Guard checks are added even at -O0. 30define i32 @func_optnone_cf() #2 { 31entry: 32 %func_ptr = alloca i32 ()*, align 8 33 store i32 ()* @target_func, i32 ()** %func_ptr, align 8 34 %0 = load i32 ()*, i32 ()** %func_ptr, align 8 35 %1 = call i32 %0() 36 ret i32 %1 37 38 ; The call to __guard_check_icall_fptr should come immediately before the call to the target function. 39 ; CHECK-LABEL: func_optnone_cf 40 ; CHECK: movw r0, :lower16:target_func 41 ; CHECK: movt r0, :upper16:target_func 42 ; CHECK: str r0, [sp] 43 ; CHECK: ldr r4, [sp] 44 ; CHECK: movw r0, :lower16:__guard_check_icall_fptr 45 ; CHECK: movt r0, :upper16:__guard_check_icall_fptr 46 ; CHECK: ldr r1, [r0] 47 ; CHECK: mov r0, r4 48 ; CHECK: blx r1 49 ; CHECK-NEXT: blx r4 50} 51attributes #2 = { noinline optnone "target-cpu"="cortex-a9" "target-features"="+armv7-a,+dsp,+fp16,+neon,+strict-align,+thumb-mode,+vfp3"} 52 53 54; Test that Control Flow Guard checks are correctly added in optimized code (common case). 55define i32 @func_cf() #0 { 56entry: 57 %func_ptr = alloca i32 ()*, align 8 58 store i32 ()* @target_func, i32 ()** %func_ptr, align 8 59 %0 = load i32 ()*, i32 ()** %func_ptr, align 8 60 %1 = call i32 %0() 61 ret i32 %1 62 63 ; The call to __guard_check_icall_fptr should come immediately before the call to the target function. 64 ; CHECK-LABEL: func_cf 65 ; CHECK: movw r0, :lower16:__guard_check_icall_fptr 66 ; CHECK: movt r0, :upper16:__guard_check_icall_fptr 67 ; CHECK: ldr r1, [r0] 68 ; CHECK: movw r4, :lower16:target_func 69 ; CHECK: movt r4, :upper16:target_func 70 ; CHECK: mov r0, r4 71 ; CHECK: blx r1 72 ; CHECK-NEXT: blx r4 73} 74 75 76; Test that Control Flow Guard checks are correctly added on invoke instructions. 77define i32 @func_cf_invoke() #0 personality i8* bitcast (void ()* @h to i8*) { 78entry: 79 %0 = alloca i32, align 4 80 %func_ptr = alloca i32 ()*, align 8 81 store i32 ()* @target_func, i32 ()** %func_ptr, align 8 82 %1 = load i32 ()*, i32 ()** %func_ptr, align 8 83 %2 = invoke i32 %1() 84 to label %invoke.cont unwind label %lpad 85invoke.cont: ; preds = %entry 86 ret i32 %2 87 88lpad: ; preds = %entry 89 %tmp = landingpad { i8*, i32 } 90 catch i8* null 91 ret i32 -1 92 93 ; The call to __guard_check_icall_fptr should come immediately before the call to the target function. 94 ; CHECK-LABEL: func_cf_invoke 95 ; CHECK: movw r0, :lower16:__guard_check_icall_fptr 96 ; CHECK: movt r0, :upper16:__guard_check_icall_fptr 97 ; CHECK: ldr r1, [r0] 98 ; CHECK: movw r4, :lower16:target_func 99 ; CHECK: movt r4, :upper16:target_func 100 ; CHECK: mov r0, r4 101 ; CHECK: blx r1 102 ; CHECK-NEXT: $Mtmp0: 103 ; CHECK-NEXT: blx r4 104 ; CHECK: ; %invoke.cont 105 ; CHECK: ; %lpad 106} 107 108declare void @h() 109 110 111; Test that longjmp targets have public labels and are included in the .gljmp section. 112%struct._SETJMP_FLOAT128 = type { [2 x i64] } 113@buf1 = internal global [16 x %struct._SETJMP_FLOAT128] zeroinitializer, align 16 114 115define i32 @func_cf_setjmp() #0 { 116 %1 = alloca i32, align 4 117 %2 = alloca i32, align 4 118 store i32 0, i32* %1, align 4 119 store i32 -1, i32* %2, align 4 120 %3 = call i8* @llvm.frameaddress(i32 0) 121 %4 = call i32 @_setjmp(i8* bitcast ([16 x %struct._SETJMP_FLOAT128]* @buf1 to i8*), i8* %3) #3 122 123 ; CHECK-LABEL: func_cf_setjmp 124 ; CHECK: bl _setjmp 125 ; CHECK-NEXT: $cfgsj_func_cf_setjmp0: 126 127 %5 = call i8* @llvm.frameaddress(i32 0) 128 %6 = call i32 @_setjmp(i8* bitcast ([16 x %struct._SETJMP_FLOAT128]* @buf1 to i8*), i8* %5) #3 129 130 ; CHECK: bl _setjmp 131 ; CHECK-NEXT: $cfgsj_func_cf_setjmp1: 132 133 store i32 1, i32* %2, align 4 134 %7 = load i32, i32* %2, align 4 135 ret i32 %7 136 137 ; CHECK: .section .gljmp$y,"dr" 138 ; CHECK-NEXT: .symidx $cfgsj_func_cf_setjmp0 139 ; CHECK-NEXT: .symidx $cfgsj_func_cf_setjmp1 140} 141 142declare i8* @llvm.frameaddress(i32) 143 144; Function Attrs: returns_twice 145declare dso_local i32 @_setjmp(i8*, i8*) #3 146 147attributes #3 = { returns_twice } 148 149 150!llvm.module.flags = !{!0} 151!0 = !{i32 2, !"cfguard", i32 2} 152