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| ; RUN: llc < %s -mtriple=i686-pc-windows-msvc | FileCheck %s -check-prefix=X32
; RUN: llc < %s -mtriple=x86_64-pc-windows-msvc | FileCheck %s -check-prefix=X64
; 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 to functions with nocf_checks attribute.
define i32 @func_nocf_checks() #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
; X32-LABEL: func_nocf_checks
; X32: movl $_target_func, %eax
; X32-NOT: __guard_check_icall_fptr
; X32: calll *%eax
; X64-LABEL: func_nocf_checks
; X64: leaq target_func(%rip), %rax
; X64-NOT: __guard_dispatch_icall_fptr
; X64: callq *%rax
}
attributes #0 = { nocf_check }
; Test that Control Flow Guard checks are added even at -O0.
; FIXME Ideally these checks should be added as a single call instruction, as in the optimized case.
define i32 @func_optnone_cf() #1 {
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
; On i686, the call to __guard_check_icall_fptr should come immediately before the call to the target function.
; X32-LABEL: func_optnone_cf
; X32: leal _target_func, %eax
; X32: movl %eax, (%esp)
; X32: movl (%esp), %ecx
; X32: movl ___guard_check_icall_fptr, %eax
; X32: calll *%eax
; X32-NEXT: calll *%ecx
; On x86_64, __guard_dispatch_icall_fptr tail calls the function, so there should be only one call instruction.
; X64-LABEL: func_optnone_cf
; X64: leaq target_func(%rip), %rax
; X64: movq __guard_dispatch_icall_fptr(%rip), %rcx
; X64: callq *%rcx
; X64-NOT: callq
}
attributes #1 = { noinline optnone }
; Test that Control Flow Guard checks are correctly added in optimized code (common case).
define i32 @func_cf() {
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
; On i686, the call to __guard_check_icall_fptr should come immediately before the call to the target function.
; X32-LABEL: func_cf
; X32: movl $_target_func, %esi
; X32: movl $_target_func, %ecx
; X32: calll *___guard_check_icall_fptr
; X32-NEXT: calll *%esi
; On x86_64, __guard_dispatch_icall_fptr tail calls the function, so there should be only one call instruction.
; X64-LABEL: func_cf
; X64: leaq target_func(%rip), %rax
; X64: callq *__guard_dispatch_icall_fptr(%rip)
; X64-NOT: callq
}
; Test that Control Flow Guard checks are correctly added on invoke instructions.
define i32 @func_cf_invoke() 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
; On i686, the call to __guard_check_icall_fptr should come immediately before the call to the target function.
; X32-LABEL: func_cf_invoke
; X32: movl $_target_func, %esi
; X32: movl $_target_func, %ecx
; X32: calll *___guard_check_icall_fptr
; X32-NEXT: calll *%esi
; X32: # %invoke.cont
; X32: # %lpad
; On x86_64, __guard_dispatch_icall_fptr tail calls the function, so there should be only one call instruction.
; X64-LABEL: func_cf_invoke
; X64: leaq target_func(%rip), %rax
; X64: callq *__guard_dispatch_icall_fptr(%rip)
; X64-NOT: callq
; X64: # %invoke.cont
; X64: # %lpad
}
declare void @h()
; Test that Control Flow Guard preserves floating point arguments.
declare double @target_func_doubles(double, double, double, double)
define double @func_cf_doubles() {
entry:
%func_ptr = alloca double (double, double, double, double)*, align 8
store double (double, double, double, double)* @target_func_doubles, double (double, double, double, double)** %func_ptr, align 8
%0 = load double (double, double, double, double)*, double (double, double, double, double)** %func_ptr, align 8
%1 = call double %0(double 1.000000e+00, double 2.000000e+00, double 3.000000e+00, double 4.000000e+00)
ret double %1
; On i686, the call to __guard_check_icall_fptr should come immediately before the call to the target function.
; X32-LABEL: func_cf_doubles
; X32: movl $_target_func_doubles, %esi
; X32: movl $_target_func_doubles, %ecx
; X32: calll *___guard_check_icall_fptr
; X32: calll *%esi
; On x86_64, __guard_dispatch_icall_fptr tail calls the function, so there should be only one call instruction.
; X64-LABEL: func_cf_doubles
; X64: leaq target_func_doubles(%rip), %rax
; X64: movsd __real@3ff0000000000000(%rip), %xmm0
; X64: movsd __real@4000000000000000(%rip), %xmm1
; X64: movsd __real@4008000000000000(%rip), %xmm2
; X64: movsd __real@4010000000000000(%rip), %xmm3
; X64: callq *__guard_dispatch_icall_fptr(%rip)
; X64-NOT: callq
}
; Test that Control Flow Guard checks are correctly added for tail calls.
define i32 @func_cf_tail() {
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 = musttail call i32 %0()
ret i32 %1
; On i686, the call to __guard_check_icall_fptr should come immediately before the call to the target function.
; X32-LABEL: func_cf_tail
; X32: movl $_target_func, %ecx
; X32: calll *___guard_check_icall_fptr
; X32: movl $_target_func, %eax
; X32: jmpl *%eax # TAILCALL
; X32-NOT: calll
; X64-LABEL: func_cf_tail
; X64: leaq target_func(%rip), %rax
; X64: movq __guard_dispatch_icall_fptr(%rip), %rcx
; X64: rex64 jmpq *%rcx # TAILCALL
; X64-NOT: callq
}
; 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() {
%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) #2
; X32-LABEL: func_cf_setjmp
; X32: calll __setjmp
; X32-NEXT: $cfgsj_func_cf_setjmp0:
; X64-LABEL: func_cf_setjmp
; X64: callq _setjmp
; X64-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) #2
; X32: calll __setjmp
; X32-NEXT: $cfgsj_func_cf_setjmp1:
; X64: callq _setjmp
; X64-NEXT: $cfgsj_func_cf_setjmp1:
store i32 1, i32* %2, align 4
%7 = load i32, i32* %2, align 4
ret i32 %7
; X32: .section .gljmp$y,"dr"
; X32-NEXT: .symidx $cfgsj_func_cf_setjmp0
; X32-NEXT: .symidx $cfgsj_func_cf_setjmp1
; X64: .section .gljmp$y,"dr"
; X64-NEXT: .symidx $cfgsj_func_cf_setjmp0
; X64-NEXT: .symidx $cfgsj_func_cf_setjmp1
}
declare i8* @llvm.frameaddress(i32)
; Function Attrs: returns_twice
declare dso_local i32 @_setjmp(i8*, i8*) #2
attributes #2 = { returns_twice }
!llvm.module.flags = !{!0}
!0 = !{i32 2, !"cfguard", i32 2}
|