[globalisel][tablegen] Finish fixing compile-time regressions by merging the matcher and emitter state machines.

Summary:
Also, made a few minor tweaks to shave off a little more cumulative memory consumption:
* All rules share a single NewMIs instead of constructing their own. Only one
  will end up using it.
* Use MIs.resize(1) instead of MIs.clear();MIs.push_back(I) and prevent
  GIM_RecordInsn from changing MIs[0].

Depends on D33764

Reviewers: rovka, vitalybuka, ab, t.p.northover, qcolombet, aditya_nandakumar

Reviewed By: ab

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D33766

llvm-svn: 307159

1 files changed, 26 insertions, 36 deletions

diff --git a/llvm/utils/TableGen/GlobalISelEmitter.cpp b/llvm/utils/TableGen/GlobalISelEmitter.cpp
index d4e487cf7de..c7eb7d02c0d 100644
--- a/llvm/utils/TableGen/GlobalISelEmitter.cpp
+++ b/llvm/utils/TableGen/GlobalISelEmitter.cpp
@@ -928,7 +928,7 @@ public:
   void emitCxxRenderStmts(raw_ostream &OS, RuleMatcher &Rule) const override {
     const OperandMatcher &Operand = Matched.getOperand(SymbolicName);
     unsigned OldInsnVarID = Rule.getInsnVarID(Operand.getInstructionMatcher());
-    OS << "      GIR_Copy, /*NewInsnID*/" << NewInsnID << ", /*OldInsnID*/"
+    OS << "    GIR_Copy, /*NewInsnID*/" << NewInsnID << ", /*OldInsnID*/"
        << OldInsnVarID << ", /*OpIdx*/" << Operand.getOperandIndex() << ", // "
        << SymbolicName << "\n";
   }
@@ -964,7 +964,7 @@ public:
   void emitCxxRenderStmts(raw_ostream &OS, RuleMatcher &Rule) const override {
     const OperandMatcher &Operand = Matched.getOperand(SymbolicName);
     unsigned OldInsnVarID = Rule.getInsnVarID(Operand.getInstructionMatcher());
-    OS << "      GIR_CopySubReg, /*NewInsnID*/" << NewInsnID
+    OS << "    GIR_CopySubReg, /*NewInsnID*/" << NewInsnID
        << ", /*OldInsnID*/" << OldInsnVarID << ", /*OpIdx*/"
        << Operand.getOperandIndex() << ", /*SubRegIdx*/" << SubReg->EnumValue
        << ", // " << SymbolicName << "\n";
@@ -1043,8 +1043,8 @@ public:
   }
 
   void emitCxxRenderStmts(raw_ostream &OS, RuleMatcher &Rule) const override {
-    OS << "      GIR_ComplexRenderer, /*InsnID*/" << InsnID
-       << ", /*RendererID*/" << RendererID << ",\n";
+    OS << "    GIR_ComplexRenderer, /*InsnID*/" << InsnID << ", /*RendererID*/"
+       << RendererID << ",\n";
   }
 };
 
@@ -1076,7 +1076,7 @@ public:
 
   void emitCxxActionStmts(raw_ostream &OS, RuleMatcher &Rule,
                           unsigned RecycleInsnID) const override {
-    OS << "      // " << *P.getSrcPattern() << "  =>  " << *P.getDstPattern()
+    OS << "    // " << *P.getSrcPattern() << "  =>  " << *P.getDstPattern()
        << "\n";
   }
 };
@@ -1123,7 +1123,7 @@ public:
   void emitCxxActionStmts(raw_ostream &OS, RuleMatcher &Rule,
                           unsigned RecycleInsnID) const override {
     if (canMutate()) {
-      OS << "      GIR_MutateOpcode, /*InsnID*/" << InsnID
+      OS << "    GIR_MutateOpcode, /*InsnID*/" << InsnID
          << ", /*RecycleInsnID*/ " << RecycleInsnID << ", /*Opcode*/"
          << I->Namespace << "::" << I->TheDef->getName() << ",\n";
 
@@ -1132,14 +1132,14 @@ public:
           auto Namespace = Def->getValue("Namespace")
                                ? Def->getValueAsString("Namespace")
                                : "";
-          OS << "      GIR_AddImplicitDef, " << InsnID << ", " << Namespace
+          OS << "    GIR_AddImplicitDef, " << InsnID << ", " << Namespace
              << "::" << Def->getName() << ",\n";
         }
         for (auto Use : I->ImplicitUses) {
           auto Namespace = Use->getValue("Namespace")
                                ? Use->getValueAsString("Namespace")
                                : "";
-          OS << "      GIR_AddImplicitUse, " << InsnID << ", " << Namespace
+          OS << "    GIR_AddImplicitUse, " << InsnID << ", " << Namespace
              << "::" << Use->getName() << ",\n";
         }
       }
@@ -1149,13 +1149,13 @@ public:
     // TODO: Simple permutation looks like it could be almost as common as
     //       mutation due to commutative operations.
 
-    OS << "      GIR_BuildMI, /*InsnID*/" << InsnID << ", /*Opcode*/"
+    OS << "    GIR_BuildMI, /*InsnID*/" << InsnID << ", /*Opcode*/"
        << I->Namespace << "::" << I->TheDef->getName() << ",\n";
     for (const auto &Renderer : OperandRenderers)
       Renderer->emitCxxRenderStmts(OS, Rule);
 
-    OS << "      GIR_MergeMemOperands, /*InsnID*/" << InsnID << ",\n"
-       << "      GIR_EraseFromParent, /*InsnID*/" << RecycleInsnID << ",\n";
+    OS << "    GIR_MergeMemOperands, /*InsnID*/" << InsnID << ",\n"
+       << "    GIR_EraseFromParent, /*InsnID*/" << RecycleInsnID << ",\n";
   }
 };
 
@@ -1169,7 +1169,7 @@ public:
 
   void emitCxxActionStmts(raw_ostream &OS, RuleMatcher &Rule,
                           unsigned RecycleInsnID) const override {
-    OS << "      GIR_ConstrainSelectedInstOperands, /*InsnID*/" << InsnID << ",\n";
+    OS << "    GIR_ConstrainSelectedInstOperands, /*InsnID*/" << InsnID << ",\n";
   }
 };
 
@@ -1187,7 +1187,7 @@ public:
 
   void emitCxxActionStmts(raw_ostream &OS, RuleMatcher &Rule,
                           unsigned RecycleInsnID) const override {
-    OS << "      GIR_ConstrainOperandRC, /*InsnID*/" << InsnID << ", /*Op*/"
+    OS << "    GIR_ConstrainOperandRC, /*InsnID*/" << InsnID << ", /*Op*/"
        << OpIdx << ", /*RC " << RC.getName() << "*/ " << RC.EnumValue << ",\n";
   }
 };
@@ -1264,21 +1264,11 @@ void RuleMatcher::emit(raw_ostream &OS) {
        << ",\n";
   }
 
-
   emitCxxCaptureStmts(OS);
 
   Matchers.front()->emitCxxPredicateExpr(OS, *this,
                                          getInsnVarID(*Matchers.front()));
 
-  OS << "    GIM_Accept,\n"
-     << "  };\n"
-     << "  State.MIs.clear();\n"
-     << "  State.MIs.push_back(&I);\n"
-     << "  DEBUG(dbgs() << \"Processing MatchTable" << CurrentMatchTableID
-     << "\\n\");\n"
-     << "  if (executeMatchTable(*this, State, MatcherInfo, MatchTable"
-     << CurrentMatchTableID << ", MRI, TRI, RBI, AvailableFeatures)) {\n";
-
   // We must also check if it's safe to fold the matched instructions.
   if (InsnVariableIDs.size() >= 2) {
     // Invert the map to create stable ordering (by var names)
@@ -1295,8 +1285,7 @@ void RuleMatcher::emit(raw_ostream &OS) {
 
     for (const auto &InsnID : InsnIDs) {
       // Reject the difficult cases until we have a more accurate check.
-      OS << "    if (!isObviouslySafeToFold(*State.MIs[" << InsnID << "]))\n"
-         << "      return false;\n";
+      OS << "    GIM_CheckIsSafeToFold, /*InsnID*/" << InsnID << ",\n";
 
       // FIXME: Emit checks to determine it's _actually_ safe to fold and/or
       //        account for unsafe cases.
@@ -1335,19 +1324,17 @@ void RuleMatcher::emit(raw_ostream &OS) {
     }
   }
 
-  OS << "    const static int64_t EmitTable" << CurrentMatchTableID << "[] = {\n";
   for (const auto &MA : Actions)
     MA->emitCxxActionStmts(OS, *this, 0);
-  OS << "      GIR_Done,\n"
-     << "    };\n"
-     << "    NewMIVector OutMIs;\n"
-     << "    DEBUG(dbgs() << \"Processing EmitTable" << CurrentMatchTableID
+  OS << "    GIR_Done,\n"
+     << "  };\n"
+     << "  State.MIs.resize(1);\n"
+     << "  DEBUG(dbgs() << \"Processing MatchTable" << CurrentMatchTableID
      << "\\n\");\n"
-     << "    executeEmitTable(OutMIs, State, EmitTable" << CurrentMatchTableID
-     << ", TII, TRI, RBI);\n";
-
-  OS << "    return true;\n";
-  OS << "  }\n\n";
+     << "  if (executeMatchTable(*this, OutMIs, State, MatcherInfo, MatchTable"
+     << CurrentMatchTableID << ", TII, MRI, TRI, RBI, AvailableFeatures)) {\n"
+     << "    return true;\n"
+     << "  }\n\n";
 }
 
 bool RuleMatcher::isHigherPriorityThan(const RuleMatcher &B) const {
@@ -2169,7 +2156,10 @@ void GlobalISelEmitter::run(raw_ostream &OS) {
         "than per-insn.\n"
      << "  AvailableFunctionFeatures = computeAvailableFunctionFeatures(&STI, "
         "&MF);\n"
-     << "  const PredicateBitset AvailableFeatures = getAvailableFeatures();\n";
+     << "  const PredicateBitset AvailableFeatures = getAvailableFeatures();\n"
+     << "  NewMIVector OutMIs;\n"
+     << "  State.MIs.clear();\n"
+     << "  State.MIs.push_back(&I);\n\n";
 
   for (auto &Rule : Rules) {
     Rule.emit(OS);