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; RUN: llc < %s -mtriple=arm-pc-windows-msvc | FileCheck %s -check-prefixes=CHECK,MSVC
; RUN: llc < %s -mtriple=arm-w64-windows-gnu | FileCheck %s -check-prefixes=CHECK,MINGW
; 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 ptr, align 8
store ptr @target_func, ptr %func_ptr, align 8
%0 = load ptr, ptr %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 ptr, align 8
store ptr @target_func, ptr %func_ptr, align 8
%0 = load ptr, ptr %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 ptr, align 8
store ptr @target_func, ptr %func_ptr, align 8
%0 = load ptr, ptr %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 ptr @h {
entry:
%0 = alloca i32, align 4
%func_ptr = alloca ptr, align 8
store ptr @target_func, ptr %func_ptr, align 8
%1 = load ptr, ptr %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 { ptr, i32 }
catch ptr 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
; MSVC-NEXT: $Mtmp0:
; MINGW-NEXT: .Ltmp0:
; 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, ptr %1, align 4
store i32 -1, ptr %2, align 4
%3 = call ptr @llvm.frameaddress(i32 0)
%4 = call i32 @_setjmp(ptr @buf1, ptr %3) #3
; CHECK-LABEL: func_cf_setjmp
; CHECK: bl _setjmp
; CHECK-NEXT: $cfgsj_func_cf_setjmp0:
%5 = call ptr @llvm.frameaddress(i32 0)
%6 = call i32 @_setjmp(ptr @buf1, ptr %5) #3
; CHECK: bl _setjmp
; CHECK-NEXT: $cfgsj_func_cf_setjmp1:
store i32 1, ptr %2, align 4
%7 = load i32, ptr %2, align 4
ret i32 %7
; CHECK: .section .gljmp$y,"dr"
; CHECK-NEXT: .symidx $cfgsj_func_cf_setjmp0
; CHECK-NEXT: .symidx $cfgsj_func_cf_setjmp1
}
declare ptr @llvm.frameaddress(i32)
; Function Attrs: returns_twice
declare dso_local i32 @_setjmp(ptr, ptr) #3
attributes #3 = { returns_twice }
!llvm.module.flags = !{!0}
!0 = !{i32 2, !"cfguard", i32 2}
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