[llvm] r180654 - Struct-path aware TBAA: change the format of TBAAStructType node.
Manman Ren
mren at apple.com
Fri Apr 26 17:26:11 PDT 2013
Author: mren
Date: Fri Apr 26 19:26:11 2013
New Revision: 180654
URL: http://llvm.org/viewvc/llvm-project?rev=180654&view=rev
Log:
Struct-path aware TBAA: change the format of TBAAStructType node.
We switch the order of offset and field type to make TBAAStructType node
(name, parent node, offset) similar to scalar TBAA node (name, parent node).
TypeIsImmutable is added to TBAAStructTag node.
Modified:
llvm/trunk/include/llvm/IR/MDBuilder.h
llvm/trunk/lib/Analysis/TypeBasedAliasAnalysis.cpp
llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/tbaa-path.ll
Modified: llvm/trunk/include/llvm/IR/MDBuilder.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/IR/MDBuilder.h?rev=180654&r1=180653&r2=180654&view=diff
==============================================================================
--- llvm/trunk/include/llvm/IR/MDBuilder.h (original)
+++ llvm/trunk/include/llvm/IR/MDBuilder.h Fri Apr 26 19:26:11 2013
@@ -159,26 +159,26 @@ public:
/// \brief Return metadata for a TBAA struct node in the type DAG
/// with the given name, a list of pairs (offset, field type in the type DAG).
MDNode *createTBAAStructTypeNode(StringRef Name,
- ArrayRef<std::pair<uint64_t, MDNode*> > Fields) {
+ ArrayRef<std::pair<MDNode*, uint64_t> > Fields) {
SmallVector<Value *, 4> Ops(Fields.size() * 2 + 1);
Type *Int64 = IntegerType::get(Context, 64);
Ops[0] = createString(Name);
for (unsigned i = 0, e = Fields.size(); i != e; ++i) {
- Ops[i * 2 + 1] = ConstantInt::get(Int64, Fields[i].first);
- Ops[i * 2 + 2] = Fields[i].second;
+ Ops[i * 2 + 1] = Fields[i].first;
+ Ops[i * 2 + 2] = ConstantInt::get(Int64, Fields[i].second);
}
return MDNode::get(Context, Ops);
}
/// \brief Return metadata for a TBAA scalar type node with the
/// given name, an offset and a parent in the TBAA type DAG.
- MDNode *createTBAAScalarTypeNode(StringRef Name, uint64_t Offset,
- MDNode *Parent) {
+ MDNode *createTBAAScalarTypeNode(StringRef Name, MDNode *Parent,
+ uint64_t Offset = 0) {
SmallVector<Value *, 4> Ops(3);
Type *Int64 = IntegerType::get(Context, 64);
Ops[0] = createString(Name);
- Ops[1] = ConstantInt::get(Int64, Offset);
- Ops[2] = Parent;
+ Ops[1] = Parent;
+ Ops[2] = ConstantInt::get(Int64, Offset);
return MDNode::get(Context, Ops);
}
Modified: llvm/trunk/lib/Analysis/TypeBasedAliasAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/TypeBasedAliasAnalysis.cpp?rev=180654&r1=180653&r2=180654&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/TypeBasedAliasAnalysis.cpp (original)
+++ llvm/trunk/lib/Analysis/TypeBasedAliasAnalysis.cpp Fri Apr 26 19:26:11 2013
@@ -134,6 +134,17 @@ namespace {
uint64_t getOffset() const {
return cast<ConstantInt>(Node->getOperand(2))->getZExtValue();
}
+ /// TypeIsImmutable - Test if this TBAAStructTagNode represents a type for
+ /// objects which are not modified (by any means) in the context where this
+ /// AliasAnalysis is relevant.
+ bool TypeIsImmutable() const {
+ if (Node->getNumOperands() < 4)
+ return false;
+ ConstantInt *CI = dyn_cast<ConstantInt>(Node->getOperand(3));
+ if (!CI)
+ return false;
+ return CI->getValue()[0];
+ }
};
/// This is a simple wrapper around an MDNode which provides a
@@ -153,14 +164,24 @@ namespace {
/// Get this TBAAStructTypeNode's field in the type DAG with
/// given offset. Update the offset to be relative to the field type.
TBAAStructTypeNode getParent(uint64_t &Offset) const {
+ // Parent can be omitted for the root node.
if (Node->getNumOperands() < 2)
return TBAAStructTypeNode();
+ // Special handling for a scalar type node.
+ if (Node->getNumOperands() <= 3) {
+ MDNode *P = dyn_cast_or_null<MDNode>(Node->getOperand(1));
+ if (!P)
+ return TBAAStructTypeNode();
+ return TBAAStructTypeNode(P);
+ }
+
// Assume the offsets are in order. We return the previous field if
// the current offset is bigger than the given offset.
unsigned TheIdx = 0;
for (unsigned Idx = 1; Idx < Node->getNumOperands(); Idx += 2) {
- uint64_t Cur = cast<ConstantInt>(Node->getOperand(Idx))->getZExtValue();
+ uint64_t Cur = cast<ConstantInt>(Node->getOperand(Idx + 1))->
+ getZExtValue();
if (Cur > Offset) {
assert(Idx >= 3 &&
"TBAAStructTypeNode::getParent should have an offset match!");
@@ -171,10 +192,10 @@ namespace {
// Move along the last field.
if (TheIdx == 0)
TheIdx = Node->getNumOperands() - 2;
- uint64_t Cur = cast<ConstantInt>(Node->getOperand(TheIdx))->
+ uint64_t Cur = cast<ConstantInt>(Node->getOperand(TheIdx + 1))->
getZExtValue();
Offset -= Cur;
- MDNode *P = dyn_cast_or_null<MDNode>(Node->getOperand(TheIdx + 1));
+ MDNode *P = dyn_cast_or_null<MDNode>(Node->getOperand(TheIdx));
if (!P)
return TBAAStructTypeNode();
return TBAAStructTypeNode(P);
@@ -376,7 +397,8 @@ bool TypeBasedAliasAnalysis::pointsToCon
// If this is an "immutable" type, we can assume the pointer is pointing
// to constant memory.
- if (!EnableStructPathTBAA && TBAANode(M).TypeIsImmutable())
+ if ((!EnableStructPathTBAA && TBAANode(M).TypeIsImmutable()) ||
+ (EnableStructPathTBAA && TBAAStructTagNode(M).TypeIsImmutable()))
return true;
return AliasAnalysis::pointsToConstantMemory(Loc, OrLocal);
@@ -392,7 +414,8 @@ TypeBasedAliasAnalysis::getModRefBehavio
// If this is an "immutable" type, we can assume the call doesn't write
// to memory.
if (const MDNode *M = CS.getInstruction()->getMetadata(LLVMContext::MD_tbaa))
- if (!EnableStructPathTBAA && TBAANode(M).TypeIsImmutable())
+ if ((!EnableStructPathTBAA && TBAANode(M).TypeIsImmutable()) ||
+ (EnableStructPathTBAA && TBAAStructTagNode(M).TypeIsImmutable()))
Min = OnlyReadsMemory;
return ModRefBehavior(AliasAnalysis::getModRefBehavior(CS) & Min);
@@ -454,20 +477,14 @@ MDNode *MDNode::getMostGenericTBAA(MDNod
MDNode *T = A;
while (T) {
PathA.push_back(T);
- if (EnableStructPathTBAA)
- T = T->getNumOperands() >= 3 ? cast_or_null<MDNode>(T->getOperand(2)) : 0;
- else
- T = T->getNumOperands() >= 2 ? cast_or_null<MDNode>(T->getOperand(1)) : 0;
+ T = T->getNumOperands() >= 2 ? cast_or_null<MDNode>(T->getOperand(1)) : 0;
}
SmallVector<MDNode *, 4> PathB;
T = B;
while (T) {
PathB.push_back(T);
- if (EnableStructPathTBAA)
- T = T->getNumOperands() >= 3 ? cast_or_null<MDNode>(T->getOperand(2)) : 0;
- else
- T = T->getNumOperands() >= 2 ? cast_or_null<MDNode>(T->getOperand(1)) : 0;
+ T = T->getNumOperands() >= 2 ? cast_or_null<MDNode>(T->getOperand(1)) : 0;
}
int IA = PathA.size() - 1;
Modified: llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/tbaa-path.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/tbaa-path.ll?rev=180654&r1=180653&r2=180654&view=diff
==============================================================================
--- llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/tbaa-path.ll (original)
+++ llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/tbaa-path.ll Fri Apr 26 19:26:11 2013
@@ -364,29 +364,29 @@ entry:
attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-frame-pointer-elim-non-leaf"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "unsafe-fp-math"="false" "use-soft-float"="false" }
!0 = metadata !{metadata !1, metadata !1, i64 0}
-!1 = metadata !{metadata !"any pointer", i64 0, metadata !2}
-!2 = metadata !{metadata !"omnipotent char", i64 0, metadata !3}
+!1 = metadata !{metadata !"any pointer", metadata !2}
+!2 = metadata !{metadata !"omnipotent char", metadata !3}
!3 = metadata !{metadata !"Simple C/C++ TBAA"}
!4 = metadata !{metadata !5, metadata !5, i64 0}
-!5 = metadata !{metadata !"long long", i64 0, metadata !2}
+!5 = metadata !{metadata !"long long", metadata !2}
!6 = metadata !{metadata !7, metadata !7, i64 0}
-!7 = metadata !{metadata !"int", i64 0, metadata !2}
+!7 = metadata !{metadata !"int", metadata !2}
!8 = metadata !{metadata !9, metadata !7, i64 4}
-!9 = metadata !{metadata !"_ZTS7StructA", i64 0, metadata !10, i64 4, metadata !7, i64 8, metadata !10, i64 12, metadata !7}
-!10 = metadata !{metadata !"short", i64 0, metadata !2}
+!9 = metadata !{metadata !"_ZTS7StructA", metadata !10, i64 0, metadata !7, i64 4, metadata !10, i64 8, metadata !7, i64 12}
+!10 = metadata !{metadata !"short", metadata !2}
!11 = metadata !{metadata !9, metadata !10, i64 0}
!12 = metadata !{metadata !13, metadata !7, i64 8}
-!13 = metadata !{metadata !"_ZTS7StructB", i64 0, metadata !10, i64 4, metadata !9, i64 20, metadata !7}
+!13 = metadata !{metadata !"_ZTS7StructB", metadata !10, i64 0, metadata !9, i64 4, metadata !7, i64 20}
!14 = metadata !{metadata !13, metadata !10, i64 4}
!15 = metadata !{metadata !13, metadata !7, i64 20}
!16 = metadata !{metadata !13, metadata !7, i64 16}
!17 = metadata !{metadata !18, metadata !7, i64 4}
-!18 = metadata !{metadata !"_ZTS7StructS", i64 0, metadata !10, i64 4, metadata !7}
+!18 = metadata !{metadata !"_ZTS7StructS", metadata !10, i64 0, metadata !7, i64 4}
!19 = metadata !{metadata !18, metadata !10, i64 0}
!20 = metadata !{metadata !21, metadata !7, i64 4}
-!21 = metadata !{metadata !"_ZTS8StructS2", i64 0, metadata !10, i64 4, metadata !7}
+!21 = metadata !{metadata !"_ZTS8StructS2", metadata !10, i64 0, metadata !7, i64 4}
!22 = metadata !{metadata !21, metadata !10, i64 0}
!23 = metadata !{metadata !24, metadata !7, i64 12}
-!24 = metadata !{metadata !"_ZTS7StructC", i64 0, metadata !10, i64 4, metadata !13, i64 28, metadata !7}
+!24 = metadata !{metadata !"_ZTS7StructC", metadata !10, i64 0, metadata !13, i64 4, metadata !7, i64 28}
!25 = metadata !{metadata !26, metadata !7, i64 12}
-!26 = metadata !{metadata !"_ZTS7StructD", i64 0, metadata !10, i64 4, metadata !13, i64 28, metadata !7, i64 32, metadata !2}
+!26 = metadata !{metadata !"_ZTS7StructD", metadata !10, i64 0, metadata !13, i64 4, metadata !7, i64 28, metadata !2, i64 32}
More information about the llvm-commits
mailing list