Magic-Mirror/llvm-capstone
1
0
Fork 0
mirror of https://github.com/capstone-engine/llvm-capstone.git synced 2024-12-28 02:37:37 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

[MemorySSA] Fix existing phis when inserting defs.

Browse Source 
Summary:
When inserting a new Def, and inserting Phis in the IDF when needed,
also mark the already existing Phis in the IDF as non-optimized, since
these may need fixing as well.
In the test attached, there is a Phi in the IDF that happens to be
trivial, and is wrongfully removed by the call to getLastDef that
follows. This is a valid situation and the existing IDF Phis need to
marked as "may need fixing" as well.
Resolves PR43044.

Reviewers: george.burgess.iv

Subscribers: Prazek, sanjoy.google, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66495

llvm-svn: 369464
This commit is contained in:
Alina Sbirlea 2019-08-20 22:29:06 +00:00
parent 4f41779cca
commit 1c528e8f1b
2 changed files with 64 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
llvm/lib/Analysis/MemorySSAUpdater.cpp
View File

@ -341,16 +341,20 @@ void MemorySSAUpdater::insertDef(MemoryDef *MD, bool RenameUses) {
IDFs.setDefiningBlocks(DefiningBlocks);
IDFs.calculate(IDFBlocks);
SmallVector<AssertingVH<MemoryPhi>, 4> NewInsertedPHIs;
for (auto *BBIDF : IDFBlocks)
if (!MSSA->getMemoryAccess(BBIDF)) {
auto *MPhi = MSSA->createMemoryPhi(BBIDF);
for (auto *BBIDF : IDFBlocks) {
auto *MPhi = MSSA->getMemoryAccess(BBIDF);
if (!MPhi) {
MPhi = MSSA->createMemoryPhi(BBIDF);
NewInsertedPHIs.push_back(MPhi);
// Add the phis created into the IDF blocks to NonOptPhis, so they are
// not optimized out as trivial by the call to getPreviousDefFromEnd
// below. Once they are complete, all these Phis are added to the
// FixupList, and removed from NonOptPhis inside fixupDefs().
NonOptPhis.insert(MPhi);
}
// Add the phis created into the IDF blocks to NonOptPhis, so they are
// not optimized out as trivial by the call to getPreviousDefFromEnd
// below. Once they are complete, all these Phis are added to the
// FixupList, and removed from NonOptPhis inside fixupDefs().
// Existing Phis in IDF may need fixing as well, and potentially be
// trivial before this insertion, hence add all IDF Phis. See PR43044.
NonOptPhis.insert(MPhi);
}
for (auto &MPhi : NewInsertedPHIs) {
auto *BBIDF = MPhi->getBlock();

52
llvm/test/Analysis/MemorySSA/PR43044.ll Normal file
View File

@ -0,0 +1,52 @@
; RUN: opt -loop-rotate -licm -enable-mssa-loop-dependency -verify-memoryssa %s -S | FileCheck %s
; REQUIRES: asserts
target datalayout = "E-m:e-i1:8:16-i8:8:16-i64:64-f128:64-v128:64-a:8:16-n32:64"
target triple = "s390x-ibm-linux"
declare void @llvm.lifetime.end.p0i8(i64 immarg, i8* nocapture)
; CHECK-LABEL: @func_42()
define void @func_42() {
entry:
br label %for.cond1050
for.cond1050.loopexit: ; preds = %for.cond1373
br label %for.cond1050
for.cond1050: ; preds = %for.cond1050.loopexit, %entry
%storemerge6 = phi i32 [ 2, %entry ], [ 0, %for.cond1050.loopexit ]
%cmp1051 = icmp sgt i32 %storemerge6, -1
br i1 %cmp1051, label %for.cond1055.preheader, label %cleanup1400.loopexit1
for.cond1055.preheader: ; preds = %for.cond1050
store i64 0, i64* null, align 8
%0 = load i64, i64* null, align 8
%tobool1383 = icmp eq i64 %0, 0
br i1 %tobool1383, label %for.cond1055.preheader.cleanup1400.loopexit.split_crit_edge, label %for.cond1055.preheader.for.cond1055.preheader.split_crit_edge
for.cond1055.preheader.for.cond1055.preheader.split_crit_edge: ; preds = %for.cond1055.preheader
br label %for.body1376
for.cond1055.preheader.cleanup1400.loopexit.split_crit_edge: ; preds = %for.cond1055.preheader
br label %cleanup1400.loopexit.split
for.cond1373: ; preds = %for.body1376
br i1 true, label %for.body1376, label %for.cond1050.loopexit
for.body1376: ; preds = %for.cond1373, %for.cond1055.preheader.for.cond1055.preheader.split_crit_edge
br i1 false, label %cleanup1400.loopexit, label %for.cond1373
cleanup1400.loopexit: ; preds = %for.body1376
br label %cleanup1400.loopexit.split
cleanup1400.loopexit.split: ; preds = %cleanup1400.loopexit, %for.cond1055.preheader.cleanup1400.loopexit.split_crit_edge
br label %cleanup1400
cleanup1400.loopexit1: ; preds = %for.cond1050
br label %cleanup1400
cleanup1400: ; preds = %cleanup1400.loopexit1, %cleanup1400.loopexit.split
call void @llvm.lifetime.end.p0i8(i64 4, i8* nonnull undef)
unreachable
}