RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2025-01-10 13:51:37 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Have ScalarEvolution use SimplifyInstruction rather than hasConstantValue.

Browse Source 
While there, add a note about an inefficiency I noticed.

llvm-svn: 119458
This commit is contained in:
Duncan Sands 2010-11-17 04:18:45 +00:00
parent a2af48a00b
commit 7376a19858
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
lib/Analysis/ScalarEvolution.cpp
View File

@ -69,6 +69,7 @@
#include "llvm/Operator.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Assembly/Writer.h"
@ -2874,7 +2875,10 @@ const SCEV *ScalarEvolution::createNodeForPHI(PHINode *PN) {
// PHI's incoming blocks are in a different loop, in which case doing so
// risks breaking LCSSA form. Instcombine would normally zap these, but
// it doesn't have DominatorTree information, so it may miss cases.
if (Value *V = PN->hasConstantValue(DT)) {
if (Value *V = SimplifyInstruction(PN, TD, DT)) {
// TODO: The following check is suboptimal. For example, it is pointless
// if V is a constant. Since the problematic case is if V is defined inside
// a deeper loop, it would be better to check for that directly.
bool AllSameLoop = true;
Loop *PNLoop = LI->getLoopFor(PN->getParent());
for (size_t i = 0, e = PN->getNumIncomingValues(); i != e; ++i)