localescape.ll
4.2 KB
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; RUN: llc -mtriple=x86_64-windows-msvc < %s | FileCheck %s --check-prefix=X64
; RUN: llc -mtriple=i686-windows-msvc < %s | FileCheck %s --check-prefix=X86
declare i8* @llvm.frameaddress(i32)
declare void @llvm.localescape(...)
declare i8* @llvm.localaddress()
declare i8* @llvm.localrecover(i8*, i8*, i32)
declare i32 @printf(i8*, ...)
@str = internal constant [10 x i8] c"asdf: %d\0A\00"
define void @print_framealloc_from_fp(i8* %fp) {
%a.i8 = call i8* @llvm.localrecover(i8* bitcast (void(i32)* @alloc_func to i8*), i8* %fp, i32 0)
%a = bitcast i8* %a.i8 to i32*
%a.val = load i32, i32* %a
call i32 (i8*, ...) @printf(i8* getelementptr ([10 x i8], [10 x i8]* @str, i32 0, i32 0), i32 %a.val)
%b.i8 = call i8* @llvm.localrecover(i8* bitcast (void(i32)* @alloc_func to i8*), i8* %fp, i32 1)
%b = bitcast i8* %b.i8 to i32*
%b.val = load i32, i32* %b
call i32 (i8*, ...) @printf(i8* getelementptr ([10 x i8], [10 x i8]* @str, i32 0, i32 0), i32 %b.val)
store i32 42, i32* %b
%b2 = getelementptr i32, i32* %b, i32 1
%b2.val = load i32, i32* %b2
call i32 (i8*, ...) @printf(i8* getelementptr ([10 x i8], [10 x i8]* @str, i32 0, i32 0), i32 %b2.val)
ret void
}
; X64-LABEL: print_framealloc_from_fp:
; X64: movq %rcx, %[[parent_fp:[a-z]+]]
; X64: movl .Lalloc_func$frame_escape_0(%rcx), %edx
; X64: leaq {{.*}}(%rip), %[[str:[a-z]+]]
; X64: movq %[[str]], %rcx
; X64: callq printf
; X64: movl .Lalloc_func$frame_escape_1(%[[parent_fp]]), %edx
; X64: movq %[[str]], %rcx
; X64: callq printf
; X64: movl $42, .Lalloc_func$frame_escape_1(%[[parent_fp]])
; X64: retq
; X86-LABEL: print_framealloc_from_fp:
; X86: pushl %esi
; X86: movl 8(%esp), %esi
; X86: pushl Lalloc_func$frame_escape_0(%esi)
; X86: pushl $_str
; X86: calll _printf
; X86: addl $8, %esp
; X86: pushl Lalloc_func$frame_escape_1(%esi)
; X86: pushl $_str
; X86: calll _printf
; X86: addl $8, %esp
; X86: movl $42, Lalloc_func$frame_escape_1(%esi)
; X86: movl $4, %eax
; X86: pushl Lalloc_func$frame_escape_1(%esi,%eax)
; X86: pushl $_str
; X86: calll _printf
; X86: addl $8, %esp
; X86: popl %esi
; X86: retl
define void @alloc_func(i32 %n) {
%a = alloca i32
%b = alloca i32, i32 2
call void (...) @llvm.localescape(i32* %a, i32* %b)
store i32 42, i32* %a
store i32 13, i32* %b
; Force usage of EBP with a dynamic alloca.
alloca i8, i32 %n
%lp = call i8* @llvm.localaddress()
call void @print_framealloc_from_fp(i8* %lp)
ret void
}
; X64-LABEL: alloc_func:
; X64: pushq %rbp
; X64: subq $16, %rsp
; X64: .seh_stackalloc 16
; X64: leaq 16(%rsp), %rbp
; X64: .seh_setframe %rbp, 16
; X64: .set .Lalloc_func$frame_escape_0, -4
; X64: .set .Lalloc_func$frame_escape_1, -12
; X64: movl $42, -4(%rbp)
; X64: movl $13, -12(%rbp)
; X64: movq %rbp, %rcx
; X64: callq print_framealloc_from_fp
; X64: retq
; X86-LABEL: alloc_func:
; X86: pushl %ebp
; X86: movl %esp, %ebp
; X86: subl $12, %esp
; X86: .set Lalloc_func$frame_escape_0, -4
; X86: .set Lalloc_func$frame_escape_1, -12
; X86: movl $42, -4(%ebp)
; X86: movl $13, -12(%ebp)
; X86: pushl %ebp
; X86: calll _print_framealloc_from_fp
; X86: movl %ebp, %esp
; X86: popl %ebp
; X86: retl
; Helper to make this a complete program so it can be compiled and tested.
define i32 @main() {
call void @alloc_func(i32 3)
ret i32 0
}
define void @alloc_func_no_frameaddr() {
%a = alloca i32
%b = alloca i32
call void (...) @llvm.localescape(i32* %a, i32* %b)
store i32 42, i32* %a
store i32 13, i32* %b
call void @print_framealloc_from_fp(i8* null)
ret void
}
; X64-LABEL: alloc_func_no_frameaddr:
; X64: subq $40, %rsp
; X64: .seh_stackalloc 40
; X64: .seh_endprologue
; X64: .set .Lalloc_func_no_frameaddr$frame_escape_0, 36
; X64: .set .Lalloc_func_no_frameaddr$frame_escape_1, 32
; X64: movl $42, 36(%rsp)
; X64: movl $13, 32(%rsp)
; X64: xorl %ecx, %ecx
; X64: callq print_framealloc_from_fp
; X64: addq $40, %rsp
; X64: retq
; X86-LABEL: alloc_func_no_frameaddr:
; X86: subl $8, %esp
; X86: .set Lalloc_func_no_frameaddr$frame_escape_0, 4
; X86: .set Lalloc_func_no_frameaddr$frame_escape_1, 0
; X86: movl $42, 4(%esp)
; X86: movl $13, (%esp)
; X86: pushl $0
; X86: calll _print_framealloc_from_fp
; X86: addl $12, %esp
; X86: retl