Infer instruction properties from single-instruction patterns.
Previously, instructions without a primary patterns wouldn't get their
properties inferred. Now, we use all single-instruction patterns for
inference, including 'def : Pat<>' instances.
This causes a lot of instruction flags to change.
- Many instructions no longer have the UnmodeledSideEffects flag because
their flags are now inferred from a pattern.
- Instructions with intrinsics will get a mayStore flag if they already
have UnmodeledSideEffects and a mayLoad flag if they already have
mayStore. This is because intrinsics properties are linear.
- Instructions with atomic_load patterns get a mayStore flag because
atomic loads can't be reordered. The correct workaround is to create
pseudo-instructions instead of using normal loads. PR13693.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162614 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/CodeGenDAGPatterns.cpp b/utils/TableGen/CodeGenDAGPatterns.cpp
index 7512ae8..5225418 100644
--- a/utils/TableGen/CodeGenDAGPatterns.cpp
+++ b/utils/TableGen/CodeGenDAGPatterns.cpp
@@ -2383,6 +2383,10 @@
AnalyzeNode(Pat->getTree(0));
}
+ void Analyze(const PatternToMatch *Pat) {
+ AnalyzeNode(Pat->getSrcPattern());
+ }
+
private:
bool IsNodeBitcast(const TreePatternNode *N) const {
if (hasSideEffects || mayLoad || mayStore || isVariadic)
@@ -2542,6 +2546,17 @@
return false;
}
+/// Get all the instructions in a tree.
+static void
+getInstructionsInTree(TreePatternNode *Tree, SmallVectorImpl<Record*> &Instrs) {
+ if (Tree->isLeaf())
+ return;
+ if (Tree->getOperator()->isSubClassOf("Instruction"))
+ Instrs.push_back(Tree->getOperator());
+ for (unsigned i = 0, e = Tree->getNumChildren(); i != e; ++i)
+ getInstructionsInTree(Tree->getChild(i), Instrs);
+}
+
/// ParseInstructions - Parse all of the instructions, inlining and resolving
/// any fragments involved. This populates the Instructions list with fully
/// resolved instructions.
@@ -2870,6 +2885,30 @@
Errors += InferFromPattern(InstInfo, PatInfo, InstInfo.TheDef);
}
+ // Second, look for single-instruction patterns defined outside the
+ // instruction.
+ for (ptm_iterator I = ptm_begin(), E = ptm_end(); I != E; ++I) {
+ const PatternToMatch &PTM = *I;
+
+ // We can only infer from single-instruction patterns, otherwise we won't
+ // know which instruction should get the flags.
+ SmallVector<Record*, 8> PatInstrs;
+ getInstructionsInTree(PTM.getDstPattern(), PatInstrs);
+ if (PatInstrs.size() != 1)
+ continue;
+
+ // Get the single instruction.
+ CodeGenInstruction &InstInfo = Target.getInstruction(PatInstrs.front());
+
+ // Only infer properties from the first pattern. We'll verify the others.
+ if (InstInfo.InferredFrom)
+ continue;
+
+ InstAnalyzer PatInfo(*this);
+ PatInfo.Analyze(&PTM);
+ Errors += InferFromPattern(InstInfo, PatInfo, PTM.getSrcRecord());
+ }
+
if (Errors)
throw "pattern conflicts";