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# RUN: llc -mtriple=x86_64-unknown-linux-gnu -mcpu=corei7 -no-stack-coloring=false -run-pass stack-coloring -o - %s
# Test to insure that the liveness analysis in the StackColoring
# pass gracefully handles statically unreachable blocks. See PR 37310.
# This MIR testcase was created by compiling the following test, first
# with "clang -emit-llvm -S" and then "llc -stop-before stack-coloring",
# and finally editing the resulting MIR by hand to introduce a statically
# unreachable BB (to wit: rename all bb.3 to bb.4, rename bb.2 to bb.3,
# then add bb.2 with unconditional jump to bb.4).
# Original C code:
# extern int inita(int *);
# void foo(int x) {
# if (x != 3) {
# int q[128];
# inita(&q[0]);
# return;
# }
# int r[128];
# inita(&r[x]);
# }
--- |
define void @foo(i32 %x) {
entry:
%q = alloca [128 x i32], align 16
%r = alloca [128 x i32], align 16
%cmp = icmp eq i32 %x, 3
br i1 %cmp, label %if.end, label %if.then
if.then: ; preds = %entry
%0 = bitcast ptr %q to ptr
call void @llvm.lifetime.start.p0(i64 512, ptr nonnull %0)
%arrayidx2 = bitcast ptr %q to ptr
%call = call i32 @inita(ptr nonnull %arrayidx2)
call void @llvm.lifetime.end.p0(i64 512, ptr nonnull %0)
br label %return
unreachable:
br label %return
if.end: ; preds = %entry
%1 = bitcast ptr %r to ptr
call void @llvm.lifetime.start.p0(i64 512, ptr nonnull %1)
%arrayidx1 = getelementptr inbounds [128 x i32], ptr %r, i64 0, i64 3
%call2 = call i32 @inita(ptr nonnull %arrayidx1)
call void @llvm.lifetime.end.p0(i64 512, ptr nonnull %1)
br label %return
return: ; preds = %if.end, %if.then
ret void
}
declare void @llvm.lifetime.start.p0(i64, ptr nocapture)
declare i32 @inita(ptr)
declare void @llvm.lifetime.end.p0(i64, ptr nocapture)
declare void @llvm.stackprotector(ptr, ptr)
...
---
name: foo
alignment: 16
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
failedISel: false
tracksRegLiveness: true
registers:
- { id: 0, class: gr32, preferred-register: '' }
- { id: 1, class: gr32, preferred-register: '' }
- { id: 2, class: gr64, preferred-register: '' }
- { id: 3, class: gr32, preferred-register: '' }
- { id: 4, class: gr64, preferred-register: '' }
- { id: 5, class: gr32, preferred-register: '' }
liveins:
- { reg: '$edi' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 0
offsetAdjustment: 0
maxAlignment: 16
adjustsStack: false
hasCalls: true
stackProtector: ''
maxCallFrameSize: 4294967295
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
localFrameSize: 0
savePoint: ''
restorePoint: ''
fixedStack:
stack:
- { id: 0, name: q, type: default, offset: 0, size: 512, alignment: 16,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 1, name: r, type: default, offset: 0, size: 512, alignment: 16,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
constants:
body: |
bb.0.entry:
successors: %bb.3(0x40000000), %bb.1(0x40000000)
liveins: $edi
%0:gr32 = COPY $edi
%1:gr32 = SUB32ri8 %0, 3, implicit-def $eflags
JCC_1 %bb.3, 4, implicit $eflags
JMP_1 %bb.1
bb.1.if.then:
successors: %bb.4(0x80000000)
LIFETIME_START %stack.0.q
ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
%2:gr64 = LEA64r %stack.0.q, 1, $noreg, 0, $noreg
$rdi = COPY %2
CALL64pcrel32 @inita, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, implicit-def $eax
ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
%3:gr32 = COPY $eax
LIFETIME_END %stack.0.q
JMP_1 %bb.4
bb.2.unreachable:
successors: %bb.4(0x80000000)
JMP_1 %bb.4
bb.3.if.end:
successors: %bb.4(0x80000000)
LIFETIME_START %stack.1.r
%4:gr64 = LEA64r %stack.1.r, 1, $noreg, 12, $noreg
ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
$rdi = COPY %4
CALL64pcrel32 @inita, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, implicit-def $eax
ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
%5:gr32 = COPY $eax
LIFETIME_END %stack.1.r
bb.4.return:
RET 0
...
|
