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
36
37
38
39
40
41
42
43
44
45
46
|
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -mcpu=z13 -O3 -misched=ilpmin -systemz-subreg-liveness -verify-machineinstrs -start-before simple-register-coalescing %s -mtriple s390x-ibm-linux -stop-after machine-scheduler -o - | FileCheck %s
# Check that when the register coalescer rematerializes a register to set
# only a sub register, it sets the subranges of the unused lanes as being dead
# at the definition point.
#
# The way that test exercises that comes in two steps:
# - First, we need the register coalescer to rematerialize something.
# In that test, %0 is rematerializable and will be rematerialized in
# %1 since %1 and %0 cannot be directly coalesced (they interfere).
# - Second, we indirectly check that the subranges are valid for %1
# when, in the machine scheduler, we move the instructions that define %1
# closer to the return instruction (i.e., we move MSFI and the rematerialized
# definition of %0 (i.e., %1 = LGHI 25) down). When doing that displacement,
# the scheduler updates the live-ranges of %1. When the subrange for the
# unused lane (here the subrange for %1.subreg_h32) was not correct, the
# scheduler would hit an assertion or access some invalid memory location
# making the compiler crash.
#
# Bottom line, this test checks what was intended if at the end, both %0 and %1
# are defined with `LGHI 25` and the instructions defining %1 are right before
# the return instruction.
#
# PR41372
---
name: main
tracksRegLiveness: true
body: |
bb.0:
; CHECK-LABEL
; CHECK-LABEL: name: main
; CHECK: [[LGHI:%[0-9]+]]:gr64bit = LGHI 25
; CHECK: CHIMux [[LGHI]].subreg_l32, 0, implicit-def $cc
; CHECK: [[LGHI1:%[0-9]+]]:gr64bit = LGHI 25
; CHECK: undef [[LGHI1]].subreg_l32:gr64bit = MSFI [[LGHI1]].subreg_l32, -117440512
; CHECK: Return implicit [[LGHI1]].subreg_l32
%0:gr64bit = LGHI 25
%1:gr32bit = COPY %0.subreg_l32
%1:gr32bit = MSFI %1, -117440512
%2:grx32bit = COPY %0.subreg_l32
CHIMux killed %2, 0, implicit-def $cc
%3:gr32bit = COPY killed %1
Return implicit %3
...
|
