maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

If the loop executes a constant number of times, try a bit harder to replace 

exit values.

llvm-svn: 13018
This commit is contained in:
Chris Lattner 2004-04-17 18:44:09 +00:00
parent 4021d1af5a
commit a814080025
1 changed files with 5 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
View File

@ -276,6 +276,8 @@ void IndVarSimplify::RewriteLoopExitValues(Loop *L) {
BasicBlock::iterator InsertPt = BlockToInsertInto->begin();
while (isa<PHINode>(InsertPt)) ++InsertPt;
bool HasConstantItCount = isa<SCEVConstant>(SE->getIterationCount(L));
std::set<Instruction*> InstructionsToDelete;
for (unsigned i = 0, e = L->getBlocks().size(); i != e; ++i)
@ -284,7 +286,8 @@ void IndVarSimplify::RewriteLoopExitValues(Loop *L) {
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
if (I->getType()->isInteger()) { // Is an integer instruction
SCEVHandle SH = SE->getSCEV(I);
if (SH->hasComputableLoopEvolution(L)) { // Varies predictably
if (SH->hasComputableLoopEvolution(L) || // Varies predictably
HasConstantItCount) {
// Find out if this predictably varying value is actually used
// outside of the loop. "extra" as opposed to "intra".
std::vector<User*> ExtraLoopUsers;