6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-06-14 14:24:05 +00:00
Code Issues Projects Releases Wiki Activity

Don't bother counting alias results, allow the AliasAnalysisCounter to do that.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5505 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner
2003-02-07 20:39:48 +00:00
parent a89feb55e0
commit 1dbd1b820f
2 changed files with 8 additions and 37 deletions
Download Patch File Download Diff File Expand all files Collapse all files

30
lib/Analysis/AliasAnalysis.cpp
View File

@ -25,14 +25,10 @@
#include "llvm/Constants.h"
#include "llvm/GlobalValue.h"
#include "llvm/DerivedTypes.h"
#include "Support/Statistic.h"
// Register the AliasAnalysis interface, providing a nice name to refer to.
namespace {
RegisterAnalysisGroup<AliasAnalysis> Z("Alias Analysis");
Statistic<> NumNoAlias ("basic-aa", "Number of 'no alias' replies");
Statistic<> NumMayAlias ("basic-aa", "Number of 'may alias' replies");
Statistic<> NumMustAlias("basic-aa", "Number of 'must alias' replies");
}
// CanModify - Define a little visitor class that is used to check to see if
@ -145,20 +141,6 @@ static const Value *getUnderlyingObject(const Value *V) {
return 0;
}
static inline AliasAnalysis::Result MustAlias() {
++NumMustAlias;
return AliasAnalysis::MustAlias;
}
static inline AliasAnalysis::Result MayAlias() {
++NumMayAlias;
return AliasAnalysis::MayAlias;
}
static inline AliasAnalysis::Result NoAlias() {
++NumNoAlias;
return AliasAnalysis::NoAlias;
}
// alias - Provide a bunch of ad-hoc rules to disambiguate in common cases, such
// as array references. Note that this function is heavily tail recursive.
@ -173,11 +155,11 @@ AliasAnalysis::Result BasicAliasAnalysis::alias(const Value *V1,
V2 = CPR->getValue();
// Are we checking for alias of the same value?
if (V1 == V2) return ::MustAlias();
if (V1 == V2) return MustAlias;
if ((!isa<PointerType>(V1->getType()) || !isa<PointerType>(V2->getType())) &&
V1->getType() != Type::LongTy && V2->getType() != Type::LongTy)
return ::NoAlias(); // Scalars cannot alias each other
return NoAlias; // Scalars cannot alias each other
// Strip off cast instructions...
if (const Instruction *I = dyn_cast<CastInst>(V1))
@ -216,7 +198,7 @@ AliasAnalysis::Result BasicAliasAnalysis::alias(const Value *V1,
//
if (AllConstant &&
alias(GEP1->getOperand(0), GEP2->getOperand(1)) != MayAlias)
return ::NoAlias();
return NoAlias;
}
// Figure out what objects these things are pointing to if we can...
@ -226,16 +208,16 @@ AliasAnalysis::Result BasicAliasAnalysis::alias(const Value *V1,
// Pointing at a discernable object?
if (O1 && O2) {
// If they are two different objects, we know that we have no alias...
if (O1 != O2) return ::NoAlias();
if (O1 != O2) return NoAlias;
// If they are the same object, they we can look at the indexes. If they
// index off of the object is the same for both pointers, they must alias.
// If they are provably different, they must not alias. Otherwise, we can't
// tell anything.
} else if (O1 && isa<ConstantPointerNull>(V2)) {
return ::NoAlias(); // Unique values don't alias null
return NoAlias; // Unique values don't alias null
} else if (O2 && isa<ConstantPointerNull>(V1)) {
return ::NoAlias(); // Unique values don't alias null
return NoAlias; // Unique values don't alias null
}
return MayAlias;