llvm/test/CodeGen/X86/probe-stack-eflags.ll

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s | FileCheck %s

target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

; https://github.com/llvm/llvm-project/issues/49509
; Stack probes must not clobber live EFLAGS. Previously, the prologue was
; inserted in %bb.2, with "subq $8, %rsp" clobbering the "sets %bl" flag.

define i32 @f(i32 %a, i32 %b) #0 {
; CHECK-LABEL: f:
; CHECK:       # %bb.0: # %bb13.i
; CHECK-NEXT:    pushq %rbp
; CHECK-NEXT:    pushq %rbx
; CHECK-NEXT:    pushq %rax
; CHECK-NEXT:    testl %edi, %edi
; CHECK-NEXT:    je .LBB0_1
; CHECK-NEXT:  # %bb.2: # %bb16.i
; CHECK-NEXT:    sets %bl
; CHECK-NEXT:    testl %esi, %esi
; CHECK-NEXT:    sets %bpl
; CHECK-NEXT:    xorl %eax, %eax
; CHECK-NEXT:    callq *%rax
; CHECK-NEXT:    movb $1, %al
; CHECK-NEXT:    testb %al, %al
; CHECK-NEXT:    xorb %bpl, %bl
; CHECK-NEXT:    testb %al, %al
; CHECK-NEXT:    xorb $1, %bl
; CHECK-NEXT:    movzbl %bl, %eax
; CHECK-NEXT:    jmp .LBB0_3
; CHECK-NEXT:  .LBB0_1:
; CHECK-NEXT:    xorl %eax, %eax
; CHECK-NEXT:  .LBB0_3: # %exit2
; CHECK-NEXT:    addq $8, %rsp
; CHECK-NEXT:    popq %rbx
; CHECK-NEXT:    popq %rbp
; CHECK-NEXT:    retq
bb13.i:
  %0 = icmp eq i32 %a, 0
  br i1 %0, label %exit2, label %bb16.i

bb16.i:                                           ; preds = %bb13.i
  %1 = icmp slt i32 %a, 0
  %2 = icmp slt i32 %b, 0
  %sign_z.i = xor i1 %1, %2
  br label %exit1

exit1: ; preds = %bb16.i
  %3 = call { i64, i64 } null()
  %4 = icmp eq i64 0, 0
  br i1 %4, label %bb41.i, label %bb33.i

bb33.i:                                           ; preds = %exit1
  %rcarry.not.i = icmp ult i64 0, 0
  br label %bb41.i

bb41.i:                                           ; preds = %bb33.i, %exit1
  br label %bb62.i

bb62.i:                                           ; preds = %bb41.i
  %_109.not.i = icmp eq i8 0, 0
  br i1 %_109.not.i, label %bb70.i, label %bb64.i

bb64.i:                                           ; preds = %bb62.i
  %5 = icmp ne i64 0, 0
  br label %bb70.i

bb70.i:                                           ; preds = %bb64.i, %bb62.i
  %spec.select.i.i = select i1 %sign_z.i, i32 0, i32 1
  br label %exit2

exit2: ; preds = %bb70.i, %bb13.i
  %.1.i = phi i32 [ %spec.select.i.i, %bb70.i ], [ 0, %bb13.i ]
  ret i32 %.1.i
}

define void @CSE_eflags_live(i64 %length) "probe-stack"="__chkstk_darwin" {
; CHECK-LABEL: CSE_eflags_live:
; CHECK:       # %bb.0: # %entry
; CHECK-NEXT:    testq %rdi, %rdi
; CHECK-NEXT:    je .LBB1_2
; CHECK-NEXT:  # %bb.1: # %if.end6
; CHECK-NEXT:    pushq %rbp
; CHECK-NEXT:    .cfi_def_cfa_offset 16
; CHECK-NEXT:    .cfi_offset %rbp, -16
; CHECK-NEXT:    movq %rsp, %rbp
; CHECK-NEXT:    .cfi_def_cfa_register %rbp
; CHECK-NEXT:    movq %rdi, %rax
; CHECK-NEXT:    sarq $63, %rax
; CHECK-NEXT:    orq %rdi, %rax
; CHECK-NEXT:    addq $15, %rax
; CHECK-NEXT:    andq $-16, %rax
; CHECK-NEXT:    callq __chkstk_darwin
; CHECK-NEXT:    subq %rax, %rsp
; CHECK-NEXT:    movq %rbp, %rsp
; CHECK-NEXT:    popq %rbp
; CHECK-NEXT:    .cfi_def_cfa %rsp, 8
; CHECK-NEXT:    .cfi_restore %rbp
; CHECK-NEXT:  .LBB1_2: # %cleanup78
; CHECK-NEXT:    retq
entry:
  %cmp4 = icmp eq i64 %length, 0
  br i1 %cmp4, label %cleanup78, label %if.end6

if.end6:
  %0 = tail call i64 @llvm.smax.i64(i64 %length, i64 -1)
  %vla = alloca i8, i64 %0, align 16
  br label %cleanup78

cleanup78:
  ret void
}

declare i64 @llvm.smax.i64(i64, i64)

attributes #0 = { nounwind "probe-stack"="inline-asm" }