Use pattern information to determine whether the use expects this
instruction to produce a result. e.g MUL8m, the instruction does not
produce a explicit result. However it produces an implicit result in
AL which would be copied to a temp. The root operator of the matching
pattern is a mul so the use would expect it to produce a result.
llvm-svn: 25458
diff --git a/llvm/utils/TableGen/DAGISelEmitter.cpp b/llvm/utils/TableGen/DAGISelEmitter.cpp
index cd05277..03ec995 100644
--- a/llvm/utils/TableGen/DAGISelEmitter.cpp
+++ b/llvm/utils/TableGen/DAGISelEmitter.cpp
@@ -2255,10 +2255,13 @@
OS << " CodeGenMap[N.getValue(" << ValNo << ")] = InFlag;\n";
if (AddedChain && HasOutFlag) {
- if (NumResults == 0) {
+ // Is this pattern expected to produce a result?
+ if (Pattern->getTypeNum(0) == MVT::isVoid ||
+ Pattern->getTypeNum(0) == MVT::Flag) {
OS << " return Result.getValue(N.ResNo+1);\n";
} else {
- OS << " if (N.ResNo < " << NumResults << ")\n";
+ OS << " if (N.ResNo < "
+ << ((NumResults > 1) ? NumResults : 1) << ")\n";
OS << " return Result.getValue(N.ResNo);\n";
OS << " else\n";
OS << " return Result.getValue(N.ResNo+1);\n";