File: cmpxchg8b_alloca_regalloc_handling.ll

package info (click to toggle)
llvm-toolchain-6.0 1%3A6.0.1-10
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 598,080 kB
  • sloc: cpp: 3,046,253; ansic: 595,057; asm: 271,965; python: 128,926; objc: 106,554; sh: 21,906; lisp: 10,191; pascal: 6,094; ml: 5,544; perl: 5,265; makefile: 2,227; cs: 2,027; xml: 686; php: 212; csh: 117
file content (35 lines) | stat: -rw-r--r-- 1,153 bytes parent folder | download | duplicates (6)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
; RUN: llc < %s -mtriple=i686-- -stackrealign -O2 | FileCheck %s
; PR28755

; Check that register allocator is able to handle that
; a-lot-of-fixed-and-reserved-registers case. We do that by
; emmiting lea before 4 cmpxchg8b operands generators.

define void @foo_alloca(i64* %a, i32 %off, i32 %n) {
  %dummy = alloca i32, i32 %n
  %addr = getelementptr inbounds i64, i64* %a, i32 %off

  %res = cmpxchg i64* %addr, i64 0, i64 1 monotonic monotonic
  ret void
}

; CHECK-LABEL: foo_alloca
; CHECK: leal    {{\(%e..,%e..,.*\)}}, [[REGISTER:%e.i]]
; CHECK-NEXT: xorl    %eax, %eax
; CHECK-NEXT: xorl    %edx, %edx
; CHECK-NEXT: xorl    %ecx, %ecx
; CHECK-NEXT: movl    $1, %ebx
; CHECK-NEXT: lock            cmpxchg8b       ([[REGISTER]])

; If we don't use index register in the address mode -
; check that we did not generate the lea.
define void @foo_alloca_direct_address(i64* %addr, i32 %n) {
  %dummy = alloca i32, i32 %n

  %res = cmpxchg i64* %addr, i64 0, i64 1 monotonic monotonic
  ret void
}

; CHECK-LABEL: foo_alloca_direct_address
; CHECK-NOT: leal    {{\(%e.*\)}}, [[REGISTER:%e.i]]
; CHECK: lock            cmpxchg8b       ([[REGISTER]])