replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[LICM] Allow AliasSetMap to contain top-level loops. 

When an outer loop gets deleted by a different pass, before LICM visits
it, we cannot clean up its sub-loops in AliasSetMap, because at the
point we receive the deleteAnalysisLoop callback for the outer loop, the loop
object is already invalid and we cannot access its sub-loops any longer.

Reviewers: asbirlea, sanjoy, chandlerc

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D61904

llvm-svn: 360704
This commit is contained in:
Florian Hahn 2019-05-14 19:41:36 +00:00
parent 030b17db66
commit 53c9d585b5
2 changed files with 55 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
llvm/lib/Transforms/Scalar/LICM.cpp
View File

@ -244,8 +244,16 @@ struct LegacyLICMPass : public LoopPass {
using llvm::Pass::doFinalization;
bool doFinalization() override {
assert(LICM.getLoopToAliasSetMap().empty() &&
auto &AliasSetMap = LICM.getLoopToAliasSetMap();
// All loops in the AliasSetMap should be cleaned up already. The only case
// where we fail to do so is if an outer loop gets deleted before LICM
// visits it.
assert(all_of(AliasSetMap,
[](LoopInvariantCodeMotion::ASTrackerMapTy::value_type &KV) {
return !KV.first->getParentLoop();
}) &&
"Didn't free loop alias sets");
AliasSetMap.clear();
return false;
}

46
llvm/test/Transforms/LICM/outer-loop-deleted-before-licm.ll Normal file
View File

@ -0,0 +1,46 @@
; RUN: opt %s -S -loop-unroll -licm | FileCheck %s
; Check that we can deal with loops where a parent loop gets deleted before it
; is visited by LICM.
define void @test() {
; CHECK-LABEL: define void @test() {
; CHECK-LABEL: entry:
; CHECK-NEXT: br label %for.body43
; CHECK-LABEL: for.body43: ; preds = %entry
; CHECK-NEXT: br label %if.else75
; CHECK-LABEL: if.else75: ; preds = %for.body43
; CHECK-NEXT: br label %for.body467
; CHECK-LABEL: for.body467: ; preds = %for.body467.for.body467_crit_edge, %if.else75
; CHECK-NEXT: br label %for.body467.for.body467_crit_edge
; CHECK-LABEL: for.body467.for.body467_crit_edge: ; preds = %for.body467
; CHECK-NEXT: br i1 false, label %for.end539, label %for.body467
; CHECK-LABEL: for.end539: ; preds = %for.body467.for.body467_crit_edge
; CHECK-NEXT: ret void
;
entry:
br label %for.body43
for.body43: ; preds = %for.end539, %entry
br label %if.else75
if.else75: ; preds = %for.body43
br label %for.body467
for.body467: ; preds = %for.body467.for.body467_crit_edge, %if.else75
br label %for.body467.for.body467_crit_edge
for.body467.for.body467_crit_edge: ; preds = %for.body467
br i1 false, label %for.end539, label %for.body467
for.end539: ; preds = %for.body467
br i1 undef, label %for.body43, label %for.end547
for.end547: ; preds = %for.body43
ret void
}