xref: /llvm-project/llvm/test/CodeGen/X86/probe-stack-eflags.ll (revision b32280baf9ef46cc0c9f1c700af4fd5c4e1e9acb)
1; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
2; RUN: llc < %s | FileCheck %s
3
4target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
5target triple = "x86_64-unknown-linux-gnu"
6
7; https://github.com/llvm/llvm-project/issues/49509
8; Stack probes must not clobber live EFLAGS. Previously, the prologue was
9; inserted in %bb.2, with "subq $8, %rsp" clobbering the "sets %bl" flag.
10
11define i32 @f(i32 %a, i32 %b) #0 {
12; CHECK-LABEL: f:
13; CHECK:       # %bb.0: # %bb13.i
14; CHECK-NEXT:    pushq %rbp
15; CHECK-NEXT:    pushq %rbx
16; CHECK-NEXT:    pushq %rax
17; CHECK-NEXT:    testl %edi, %edi
18; CHECK-NEXT:    je .LBB0_1
19; CHECK-NEXT:  # %bb.2: # %bb16.i
20; CHECK-NEXT:    sets %bl
21; CHECK-NEXT:    testl %esi, %esi
22; CHECK-NEXT:    sets %bpl
23; CHECK-NEXT:    xorl %eax, %eax
24; CHECK-NEXT:    callq *%rax
25; CHECK-NEXT:    movb $1, %al
26; CHECK-NEXT:    testb %al, %al
27; CHECK-NEXT:    xorb %bpl, %bl
28; CHECK-NEXT:    testb %al, %al
29; CHECK-NEXT:    xorb $1, %bl
30; CHECK-NEXT:    movzbl %bl, %eax
31; CHECK-NEXT:    jmp .LBB0_3
32; CHECK-NEXT:  .LBB0_1:
33; CHECK-NEXT:    xorl %eax, %eax
34; CHECK-NEXT:  .LBB0_3: # %exit2
35; CHECK-NEXT:    addq $8, %rsp
36; CHECK-NEXT:    popq %rbx
37; CHECK-NEXT:    popq %rbp
38; CHECK-NEXT:    retq
39bb13.i:
40  %0 = icmp eq i32 %a, 0
41  br i1 %0, label %exit2, label %bb16.i
42
43bb16.i:                                           ; preds = %bb13.i
44  %1 = icmp slt i32 %a, 0
45  %2 = icmp slt i32 %b, 0
46  %sign_z.i = xor i1 %1, %2
47  br label %exit1
48
49exit1: ; preds = %bb16.i
50  %3 = call { i64, i64 } null()
51  %4 = icmp eq i64 0, 0
52  br i1 %4, label %bb41.i, label %bb33.i
53
54bb33.i:                                           ; preds = %exit1
55  %rcarry.not.i = icmp ult i64 0, 0
56  br label %bb41.i
57
58bb41.i:                                           ; preds = %bb33.i, %exit1
59  br label %bb62.i
60
61bb62.i:                                           ; preds = %bb41.i
62  %_109.not.i = icmp eq i8 0, 0
63  br i1 %_109.not.i, label %bb70.i, label %bb64.i
64
65bb64.i:                                           ; preds = %bb62.i
66  %5 = icmp ne i64 0, 0
67  br label %bb70.i
68
69bb70.i:                                           ; preds = %bb64.i, %bb62.i
70  %spec.select.i.i = select i1 %sign_z.i, i32 0, i32 1
71  br label %exit2
72
73exit2: ; preds = %bb70.i, %bb13.i
74  %.1.i = phi i32 [ %spec.select.i.i, %bb70.i ], [ 0, %bb13.i ]
75  ret i32 %.1.i
76}
77
78define void @CSE_eflags_live(i64 %length) "probe-stack"="__chkstk_darwin" {
79; CHECK-LABEL: CSE_eflags_live:
80; CHECK:       # %bb.0: # %entry
81; CHECK-NEXT:    pushq %rbp
82; CHECK-NEXT:    .cfi_def_cfa_offset 16
83; CHECK-NEXT:    .cfi_offset %rbp, -16
84; CHECK-NEXT:    movq %rsp, %rbp
85; CHECK-NEXT:    .cfi_def_cfa_register %rbp
86; CHECK-NEXT:    testq %rdi, %rdi
87; CHECK-NEXT:    je .LBB1_2
88; CHECK-NEXT:  # %bb.1: # %if.end6
89; CHECK-NEXT:    movq $-1, %rax
90; CHECK-NEXT:    cmovnsq %rdi, %rax
91; CHECK-NEXT:    addq $15, %rax
92; CHECK-NEXT:    andq $-16, %rax
93; CHECK-NEXT:    callq __chkstk_darwin
94; CHECK-NEXT:    subq %rax, %rsp
95; CHECK-NEXT:  .LBB1_2: # %cleanup78
96; CHECK-NEXT:    movq %rbp, %rsp
97; CHECK-NEXT:    popq %rbp
98; CHECK-NEXT:    .cfi_def_cfa %rsp, 8
99; CHECK-NEXT:    retq
100entry:
101  %cmp4 = icmp eq i64 %length, 0
102  br i1 %cmp4, label %cleanup78, label %if.end6
103
104if.end6:
105  %0 = tail call i64 @llvm.smax.i64(i64 %length, i64 -1)
106  %vla = alloca i8, i64 %0, align 16
107  br label %cleanup78
108
109cleanup78:
110  ret void
111}
112
113declare i64 @llvm.smax.i64(i64, i64)
114
115attributes #0 = { nounwind "probe-stack"="inline-asm" }
116