[TableGen][AsmMatcherEmitter] Only choose specific diagnostic for enabled instruction

Summary:
When emitting a diagnostic for an invalid operand, a specific diagnostic
should only be reported when the instruction being matched is actually
enabled by the feature flags.

Patch [3/4] in a series to add parsing of predicates and properly parse SVE 
ZIP1/ZIP2 instructions. This patch fixes bogus diagnostic messages for when
the SVE feature is not specified.

Reviewers: rengolin, craig.topper, olista01, sdardis, stoklund

Reviewed By: olista01, sdardis

Subscribers: fhahn, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D40362

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320986 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 5 deletions

diff --git a/utils/TableGen/AsmMatcherEmitter.cpp b/utils/TableGen/AsmMatcherEmitter.cpp
index 1a820a54c60..0143d916a00 100644
--- a/utils/TableGen/AsmMatcherEmitter.cpp
+++ b/utils/TableGen/AsmMatcherEmitter.cpp
@@ -3269,7 +3269,9 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
   OS << "  for (const MatchEntry *it = MnemonicRange.first, "
      << "*ie = MnemonicRange.second;\n";
   OS << "       it != ie; ++it) {\n";
-
+  OS << "    bool HasRequiredFeatures =\n";
+  OS << "      (AvailableFeatures & it->RequiredFeatures) == "
+        "it->RequiredFeatures;\n";
   OS << "    DEBUG_WITH_TYPE(\"asm-matcher\", dbgs() << \"Trying to match opcode \"\n";
   OS << "                                          << MII.getName(it->Opcode) << \"\\n\");\n";
 
@@ -3360,7 +3362,8 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
   OS << "        }\n";
   OS << "        // If the target matcher returned a specific error code use\n";
   OS << "        // that, else use the one from the generic matcher.\n";
-  OS << "        if (TargetDiag != Match_InvalidOperand)\n";
+  OS << "        if (TargetDiag != Match_InvalidOperand && "
+        "HasRequiredFeatures)\n";
   OS << "          Diag = TargetDiag;\n";
   OS << "      }\n";
   OS << "      // If current formal operand wasn't matched and it is optional\n"
@@ -3402,7 +3405,8 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
     OS << "      // target predicate, that diagnostic is preferred.\n";
     OS << "      if (!HadMatchOtherThanPredicate &&\n";
     OS << "          (it == MnemonicRange.first || ErrorInfo <= ActualIdx)) {\n";
-    OS << "        if (Diag != Match_InvalidOperand || ErrorInfo != ActualIdx)\n";
+    OS << "        if (HasRequiredFeatures && (ErrorInfo != ActualIdx || Diag "
+          "!= Match_InvalidOperand))\n";
     OS << "          RetCode = Diag;\n";
     OS << "        ErrorInfo = ActualIdx;\n";
     OS << "      }\n";
@@ -3423,8 +3427,7 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
   OS << "    }\n";
 
   // Emit check that the required features are available.
-  OS << "    if ((AvailableFeatures & it->RequiredFeatures) "
-     << "!= it->RequiredFeatures) {\n";
+  OS << "    if (!HasRequiredFeatures) {\n";
   if (!ReportMultipleNearMisses)
     OS << "      HadMatchOtherThanFeatures = true;\n";
   OS << "      uint64_t NewMissingFeatures = it->RequiredFeatures & "