[X86] Add test case for PR30290s failing behaviour

Following the advice in review D45022, this currently tests for the broken llc
output where an instruction is mis-scheduled. This test is committed in advance
to improve the eventual fixing patch in D45022, making the bad behaviour that
that patch fixes clearer.

llvm-svn: 331514
This commit is contained in:
Jeremy Morse 2018-05-04 10:05:10 +00:00
parent 9c116180a4
commit 07e8daa66b
1 changed files with 44 additions and 0 deletions
llvm/test/CodeGen/X86

View File

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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -mcpu=btver2 %s -o - | FileCheck %s
; Test desc: two functions (foo, bar) with byval arguments, should not have
; reads/writes from/to byval storage re-ordered.
; When broken, five "1" constants are written into the byval %struct.face,
; but the subsequent byval read of that struct (call to bar) gets re-ordered
; before those writes, illegally.
;
; FIXME: the output shown below is the broken output of llc, "movl $1" is
; scheduled after the copy between byval arguments starts. This will be fixed
; with the patch in review D45022.
source_filename = "test.c"
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-linux-gnu"
%struct.face = type { [7 x i32] }
; Function Attrs: noinline nounwind uwtable
declare void @bar(%struct.face* byval nocapture readonly align 8);
; Function Attrs: noinline nounwind uwtable
define void @foo(%struct.face* byval nocapture align 8) local_unnamed_addr {
; CHECK-LABEL: foo:
; CHECK: # %bb.0:
; CHECK-NEXT: subq $40, %rsp
; CHECK-NEXT: .cfi_def_cfa_offset 48
; CHECK-NEXT: vmovaps {{.*#+}} xmm0 = [1,1,1,1]
; CHECK-NEXT: vmovaps %xmm0, {{[0-9]+}}(%rsp)
; CHECK-NEXT: vmovups {{[0-9]+}}(%rsp), %xmm0
; CHECK-NEXT: movl $1, {{[0-9]+}}(%rsp)
; CHECK-NEXT: vmovups %xmm0, {{[0-9]+}}(%rsp)
; CHECK-NEXT: vmovaps {{[0-9]+}}(%rsp), %xmm0
; CHECK-NEXT: vmovups %xmm0, (%rsp)
; CHECK-NEXT: callq bar
; CHECK-NEXT: addq $40, %rsp
; CHECK-NEXT: .cfi_def_cfa_offset 8
; CHECK-NEXT: retq
%2 = bitcast %struct.face* %0 to <4 x i32>*
store <4 x i32> <i32 1, i32 1, i32 1, i32 1>, <4 x i32>* %2, align 8
%3 = getelementptr inbounds %struct.face, %struct.face* %0, i64 0, i32 0, i64 4
store i32 1, i32* %3, align 8
call void @bar(%struct.face* byval nonnull align 8 %0)
ret void
}