add a new OPC_SwitchOpcode which is semantically equivalent
to a scope where every child starts with a CheckOpcode, but
executes more efficiently. Enhance DAGISelMatcherOpt to
form it.
This also fixes a bug in CheckOpcode: apparently the SDNodeInfo
objects are not pointer comparable, we have to compare the
enum name.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97438 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/DAGISelMatcherEmitter.cpp b/utils/TableGen/DAGISelMatcherEmitter.cpp
index 5b435fe..a828db3 100644
--- a/utils/TableGen/DAGISelMatcherEmitter.cpp
+++ b/utils/TableGen/DAGISelMatcherEmitter.cpp
@@ -158,8 +158,8 @@
TmpBuf.clear();
raw_svector_ostream OS(TmpBuf);
formatted_raw_ostream FOS(OS);
- ChildSize = EmitMatcherList(cast<ScopeMatcher>(N)->getChild(i),
- Indent+1, CurrentIdx+VBRSize, FOS);
+ ChildSize = EmitMatcherList(SM->getChild(i), Indent+1,
+ CurrentIdx+VBRSize, FOS);
} while (GetVBRSize(ChildSize) != VBRSize);
assert(ChildSize != 0 && "Should not have a zero-sized child!");
@@ -235,6 +235,53 @@
<< cast<CheckOpcodeMatcher>(N)->getOpcode().getEnumName() << ",\n";
return 2;
+ case Matcher::SwitchOpcode: {
+ unsigned StartIdx = CurrentIdx;
+ const SwitchOpcodeMatcher *SOM = cast<SwitchOpcodeMatcher>(N);
+ OS << "OPC_SwitchOpcode /*" << SOM->getNumCases() << " cases */, ";
+ ++CurrentIdx;
+
+ // For each case we emit the size, then the opcode, then the matcher.
+ for (unsigned i = 0, e = SOM->getNumCases(); i != e; ++i) {
+ // We need to encode the opcode and the offset of the case code before
+ // emitting the case code. Handle this by buffering the output into a
+ // string while we get the size. Unfortunately, the offset of the
+ // children depends on the VBR size of the child, so for large children we
+ // have to iterate a bit.
+ SmallString<128> TmpBuf;
+ unsigned ChildSize = 0;
+ unsigned VBRSize = 0;
+ do {
+ VBRSize = GetVBRSize(ChildSize);
+
+ TmpBuf.clear();
+ raw_svector_ostream OS(TmpBuf);
+ formatted_raw_ostream FOS(OS);
+ ChildSize = EmitMatcherList(SOM->getCaseMatcher(i),
+ Indent+1, CurrentIdx+VBRSize+1, FOS);
+ } while (GetVBRSize(ChildSize) != VBRSize);
+
+ assert(ChildSize != 0 && "Should not have a zero-sized child!");
+
+ if (i != 0)
+ OS.PadToColumn(Indent*2) << "/*SwitchOpcode*/ ";
+
+ // Emit the VBR.
+ CurrentIdx += EmitVBRValue(ChildSize, OS);
+
+ OS << " " << SOM->getCaseOpcode(i).getEnumName() << ",";
+ OS << "// ->" << CurrentIdx+ChildSize+1 << '\n';
+ ++CurrentIdx;
+ OS << TmpBuf.str();
+ CurrentIdx += ChildSize;
+ }
+
+ // Emit the final zero to terminate the switch.
+ OS.PadToColumn(Indent*2) << "0, // EndSwitchOpcode\n";
+ ++CurrentIdx;
+ return CurrentIdx-StartIdx;
+ }
+
case Matcher::CheckMultiOpcode: {
const CheckMultiOpcodeMatcher *CMO = cast<CheckMultiOpcodeMatcher>(N);
OS << "OPC_CheckMultiOpcode, " << CMO->getNumOpcodes() << ", ";
@@ -575,6 +622,7 @@
OS << "OPC_CheckPatternPredicate"; break;
case Matcher::CheckPredicate: OS << "OPC_CheckPredicate"; break;
case Matcher::CheckOpcode: OS << "OPC_CheckOpcode"; break;
+ case Matcher::SwitchOpcode: OS << "OPC_SwitchOpcode"; break;
case Matcher::CheckMultiOpcode: OS << "OPC_CheckMultiOpcode"; break;
case Matcher::CheckType: OS << "OPC_CheckType"; break;
case Matcher::CheckChildType: OS << "OPC_CheckChildType"; break;