6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2026-04-21 23:17:16 +00:00
Code Issues Projects Releases Wiki Activity

Teach SCEVExpander to expand arithmetic involving pointers into GEP

Browse Source 
instructions. It attempts to create high-level multi-operand GEPs,
though in cases where this isn't possible it falls back to casting
the pointer to i8* and emitting a GEP with that. Using GEP instructions
instead of ptrtoint+arithmetic+inttoptr helps pointer analyses that
don't use ScalarEvolution, such as BasicAliasAnalysis.

Also, make the AddrModeMatcher more aggressive in handling GEPs.
Previously it assumed that operand 0 of a GEP would require a register
in almost all cases. It now does extra checking and can do more
matching if operand 0 of the GEP is foldable. This fixes a problem
that was exposed by SCEVExpander using GEPs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72093 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman
2009-05-19 02:15:55 +00:00
parent fb57f1c8ec
commit 5be18e8476
9 changed files with 270 additions and 72 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/Transforms/Scalar/IndVarSimplify.cpp
+6 -6
View File
@@ -172,7 +172,7 @@ ICmpInst *IndVarSimplify::LinearFunctionTestReplace(Loop *L,
// Expand the code for the iteration count into the preheader of the loop.
BasicBlock *Preheader = L->getLoopPreheader();
Value *ExitCnt = Rewriter.expandCodeFor(RHS, IndVar->getType(),
Value *ExitCnt = Rewriter.expandCodeFor(RHS, CmpIndVar->getType(),
Preheader->getTerminator());
// Insert a new icmp_ne or icmp_eq instruction before the branch.
@@ -218,7 +218,7 @@ void IndVarSimplify::RewriteLoopExitValues(Loop *L,
// Scan all of the instructions in the loop, looking at those that have
// extra-loop users and which are recurrences.
SCEVExpander Rewriter(*SE, *LI);
SCEVExpander Rewriter(*SE);
// We insert the code into the preheader of the loop if the loop contains
// multiple exit blocks, or in the exit block if there is exactly one.
@@ -386,7 +386,7 @@ bool IndVarSimplify::runOnLoop(Loop *L, LPPassManager &LPM) {
}
// Create a rewriter object which we'll use to transform the code with.
SCEVExpander Rewriter(*SE, *LI);
SCEVExpander Rewriter(*SE);
// Now that we know the largest of of the induction variable expressions
// in this loop, insert a canonical induction variable of the largest size.
@@ -478,7 +478,7 @@ void IndVarSimplify::RewriteIVExpressions(Loop *L, const Type *LargestType,
BasicBlock::iterator I = Rewriter.getInsertionPoint();
// Expand loop-invariant values in the loop preheader. They will
// be sunk to the exit block later, if possible.
NewVal =
NewVal =
Rewriter.expandCodeFor(AR, LargestType,
L->getLoopPreheader()->getTerminator());
Rewriter.setInsertionPoint(I);
@@ -523,7 +523,7 @@ void IndVarSimplify::RewriteIVExpressions(Loop *L, const Type *LargestType,
NewAR = SE->getAddExpr(NewAR, PromotedOffset);
// Expand the addrec into instructions.
Value *V = Rewriter.expandCodeFor(NewAR, LargestType);
Value *V = Rewriter.expandCodeFor(NewAR);
// Insert an explicit cast if necessary to truncate the value
// down to the original stride type. This is done outside of
@@ -533,7 +533,7 @@ void IndVarSimplify::RewriteIVExpressions(Loop *L, const Type *LargestType,
if (SE->getTypeSizeInBits(IVTy) != SE->getTypeSizeInBits(LargestType))
NewAR = SE->getTruncateExpr(NewAR, IVTy);
if (Rewriter.isInsertedExpression(NewAR))
V = Rewriter.expandCodeFor(NewAR, IVTy);
V = Rewriter.expandCodeFor(NewAR);
else {
V = Rewriter.InsertCastOfTo(CastInst::getCastOpcode(V, false,
IVTy, false),