[GISel][AArch64] Allow PatLeafs to be imported in GISel which were previously causing warnings (#140935)

Previously PatLeafs could not be imported, causing the following
warnings to be emitted when running tblgen with
`-warn-on-skipped-patterns:`
```
/work/clean/llvm/lib/Target/AArch64/AArch64InstrInfo.td:2631:1: warning: Skipped pattern: Src pattern child has unsupported predicate
def : Pat<(i64 (mul top32Zero:$Rn, top32Zero:$Rm)),
^
```
These changes allow the patterns to now be imported successfully.

8 files changed, 132 insertions, 10 deletions

diff --git a/llvm/utils/TableGen/Common/CodeGenDAGPatterns.cpp b/llvm/utils/TableGen/Common/CodeGenDAGPatterns.cpp
index a87aa8b..d33c0db 100644
--- a/llvm/utils/TableGen/Common/CodeGenDAGPatterns.cpp
+++ b/llvm/utils/TableGen/Common/CodeGenDAGPatterns.cpp
@@ -899,6 +899,11 @@ TreePredicateFn::TreePredicateFn(TreePattern *N) : PatFragRec(N) {
   assert(
       (!hasPredCode() || !hasImmCode()) &&
       ".td file corrupt: can't have a node predicate *and* an imm predicate");
+
+  if (hasGISelPredicateCode() && hasGISelLeafPredicateCode())
+    PrintFatalError(getOrigPatFragRecord()->getRecord()->getLoc(),
+                    ".td file corrupt: can't have GISelPredicateCode *and* "
+                    "GISelLeafPredicateCode");
 }
 
 bool TreePredicateFn::hasPredCode() const {
@@ -1293,8 +1298,20 @@ bool TreePredicateFn::hasGISelPredicateCode() const {
 }
 
 std::string TreePredicateFn::getGISelPredicateCode() const {
-  return std::string(
-      PatFragRec->getRecord()->getValueAsString("GISelPredicateCode"));
+  return PatFragRec->getRecord()->getValueAsString("GISelPredicateCode").str();
+}
+
+bool TreePredicateFn::hasGISelLeafPredicateCode() const {
+  return PatFragRec->getRecord()
+      ->getValueAsOptionalString("GISelLeafPredicateCode")
+      .has_value();
+}
+
+std::string TreePredicateFn::getGISelLeafPredicateCode() const {
+  return PatFragRec->getRecord()
+      ->getValueAsOptionalString("GISelLeafPredicateCode")
+      .value_or(StringRef())
+      .str();
 }
 
 StringRef TreePredicateFn::getImmType() const {
diff --git a/llvm/utils/TableGen/Common/CodeGenDAGPatterns.h b/llvm/utils/TableGen/Common/CodeGenDAGPatterns.h
index 725414f..a5aadf2 100644
--- a/llvm/utils/TableGen/Common/CodeGenDAGPatterns.h
+++ b/llvm/utils/TableGen/Common/CodeGenDAGPatterns.h
@@ -590,6 +590,11 @@ public:
   bool hasGISelPredicateCode() const;
   std::string getGISelPredicateCode() const;
 
+  // If true, indicates that GlobalISel-based C++ code was supplied for checking
+  // register operands.
+  bool hasGISelLeafPredicateCode() const;
+  std::string getGISelLeafPredicateCode() const;
+
 private:
   bool hasPredCode() const;
   bool hasImmCode() const;
diff --git a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.cpp b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.cpp
index 2cb3579..327ac5f 100644
--- a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.cpp
+++ b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.cpp
@@ -33,6 +33,8 @@ Error failUnsupported(const Twine &Reason) {
 std::string getEnumNameForPredicate(const TreePredicateFn &Predicate) {
   if (Predicate.hasGISelPredicateCode())
     return "GICXXPred_MI_" + Predicate.getFnName();
+  if (Predicate.hasGISelLeafPredicateCode())
+    return "GICXXPred_MO_" + Predicate.getFnName();
   return "GICXXPred_" + Predicate.getImmTypeIdentifier().str() + "_" +
          Predicate.getFnName();
 }
@@ -1326,6 +1328,19 @@ void OperandImmPredicateMatcher::emitPredicateOpcodes(MatchTable &Table,
         << MatchTable::LineBreak;
 }
 
+//===- OperandLeafPredicateMatcher
+//-----------------------------------------===//
+
+void OperandLeafPredicateMatcher::emitPredicateOpcodes(
+    MatchTable &Table, RuleMatcher &Rule) const {
+  Table << MatchTable::Opcode("GIM_CheckLeafOperandPredicate")
+        << MatchTable::Comment("MI") << MatchTable::ULEB128Value(InsnVarID)
+        << MatchTable::Comment("MO") << MatchTable::ULEB128Value(OpIdx)
+        << MatchTable::Comment("Predicate")
+        << MatchTable::NamedValue(2, getEnumNameForPredicate(Predicate))
+        << MatchTable::LineBreak;
+}
+
 //===- OperandMatcher -----------------------------------------------------===//
 
 std::string OperandMatcher::getOperandExpr(unsigned InsnVarID) const {
diff --git a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.h b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.h
index fd24459..6647257 100644
--- a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.h
+++ b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.h
@@ -824,6 +824,7 @@ public:
     IPM_OneUse,
     IPM_GenericPredicate,
     IPM_MIFlags,
+    OPM_LeafPredicate,
     OPM_SameOperand,
     OPM_ComplexPattern,
     OPM_IntrinsicID,
@@ -1255,6 +1256,26 @@ public:
                             RuleMatcher &Rule) const override;
 };
 
+/// Generates code to check that this operand is a register whose value meets
+/// the predicate.
+class OperandLeafPredicateMatcher : public OperandPredicateMatcher {
+protected:
+  TreePredicateFn Predicate;
+
+public:
+  OperandLeafPredicateMatcher(unsigned InsnVarID, unsigned OpIdx,
+                              const TreePredicateFn &Predicate)
+      : OperandPredicateMatcher(OPM_LeafPredicate, InsnVarID, OpIdx),
+        Predicate(Predicate) {}
+
+  static bool classof(const PredicateMatcher *P) {
+    return P->getKind() == OPM_LeafPredicate;
+  }
+
+  void emitPredicateOpcodes(MatchTable &Table,
+                            RuleMatcher &Rule) const override;
+};
+
 /// Generates code to check that a set of predicates match for a particular
 /// operand.
 class OperandMatcher : public PredicateListMatcher<OperandPredicateMatcher> {
diff --git a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTableExecutorEmitter.cpp b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTableExecutorEmitter.cpp
index ffab2fd..333d956 100644
--- a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTableExecutorEmitter.cpp
+++ b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTableExecutorEmitter.cpp
@@ -182,6 +182,7 @@ void GlobalISelMatchTableExecutorEmitter::emitExecutorImpl(
   emitSubtargetFeatureBitsetImpl(OS, Rules);
   emitComplexPredicates(OS, ComplexOperandMatchers);
   emitMIPredicateFns(OS);
+  emitLeafPredicateFns(OS);
   emitI64ImmPredicateFns(OS);
   emitAPFloatImmPredicateFns(OS);
   emitAPIntImmPredicateFns(OS);
@@ -234,6 +235,9 @@ void GlobalISelMatchTableExecutorEmitter::emitTemporariesDecl(
      << "  bool testMIPredicate_MI(unsigned PredicateID, const MachineInstr &MI"
         ", const MatcherState &State) "
         "const override;\n"
+     << "  bool testMOPredicate_MO(unsigned PredicateID, const MachineOperand "
+        "&MO, const MatcherState &State) "
+        "const override;\n"
      << "  bool testSimplePredicate(unsigned PredicateID) const override;\n"
      << "  bool runCustomAction(unsigned FnID, const MatcherState &State, "
         "NewMIVector &OutMIs) "
diff --git a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTableExecutorEmitter.h b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTableExecutorEmitter.h
index 862f1e8..1f66d73 100644
--- a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTableExecutorEmitter.h
+++ b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTableExecutorEmitter.h
@@ -79,8 +79,8 @@ class GlobalISelMatchTableExecutorEmitter {
       raw_ostream &OS, StringRef TypeIdentifier, StringRef ArgType,
       StringRef ArgName, StringRef AdditionalArgs,
       StringRef AdditionalDeclarations, ArrayRef<PredicateObject> Predicates,
-      std::function<StringRef(PredicateObject)> GetPredEnumName,
-      std::function<StringRef(PredicateObject)> GetPredCode,
+      llvm::function_ref<StringRef(PredicateObject)> GetPredEnumName,
+      llvm::function_ref<StringRef(PredicateObject)> GetPredCode,
       StringRef Comment) {
     if (!Comment.empty())
       OS << "// " << Comment << "\n";
@@ -135,14 +135,34 @@ protected:
   void emitMIPredicateFnsImpl(
       raw_ostream &OS, StringRef AdditionalDecls,
       ArrayRef<PredicateObject> Predicates,
-      std::function<StringRef(PredicateObject)> GetPredEnumName,
-      std::function<StringRef(PredicateObject)> GetPredCode,
+      llvm::function_ref<StringRef(PredicateObject)> GetPredEnumName,
+      llvm::function_ref<StringRef(PredicateObject)> GetPredCode,
       StringRef Comment = "") {
     return emitCxxPredicateFns(
         OS, "MI", "const MachineInstr &", "MI", ", const MatcherState &State",
         AdditionalDecls, Predicates, GetPredEnumName, GetPredCode, Comment);
   }
 
+  /// Emits `testMOPredicate_MO`.
+  /// \tparam PredicateObject An object representing a predicate to emit.
+  /// \param OS Output stream.
+  /// \param AdditionalDecls Additional C++ variable declarations.
+  /// \param Predicates Predicates to emit.
+  /// \param GetPredEnumName Returns an enum name for a given predicate.
+  /// \param GetPredCode Returns the C++ code of a given predicate.
+  /// \param Comment Optional comment for the enum declaration.
+  template <typename PredicateObject>
+  void emitLeafPredicateFnsImpl(
+      raw_ostream &OS, StringRef AdditionalDecls,
+      ArrayRef<PredicateObject> Predicates,
+      llvm::function_ref<StringRef(PredicateObject)> GetPredEnumName,
+      llvm::function_ref<StringRef(PredicateObject)> GetPredCode,
+      StringRef Comment = "") {
+    return emitCxxPredicateFns(
+        OS, "MO", "const MachineOperand &", "MO", ", const MatcherState &State",
+        AdditionalDecls, Predicates, GetPredEnumName, GetPredCode, Comment);
+  }
+
   /// Helper function to emit the following executor functions:
   ///   * testImmPredicate_I64      (TypeIdentifier=I64)
   ///   * testImmPredicate_APInt    (TypeIdentifier=APInt)
@@ -160,8 +180,8 @@ protected:
   void emitImmPredicateFnsImpl(
       raw_ostream &OS, StringRef TypeIdentifier, StringRef ArgType,
       ArrayRef<PredicateObject> Predicates,
-      std::function<StringRef(PredicateObject)> GetPredEnumName,
-      std::function<StringRef(PredicateObject)> GetPredCode,
+      llvm::function_ref<StringRef(PredicateObject)> GetPredEnumName,
+      llvm::function_ref<StringRef(PredicateObject)> GetPredCode,
       StringRef Comment = "") {
     return emitCxxPredicateFns(OS, TypeIdentifier, ArgType, "Imm", "", "",
                                Predicates, GetPredEnumName, GetPredCode,
@@ -189,6 +209,10 @@ public:
   /// Note: `emitMIPredicateFnsImpl` can be used to do most of the work.
   virtual void emitMIPredicateFns(raw_ostream &OS) = 0;
 
+  /// Emit the `testLeafPredicate` function
+  /// Note `emitLeafPredicateFnsImpl` can be used to do most of the work.
+  virtual void emitLeafPredicateFns(raw_ostream &OS) = 0;
+
   /// Emit the `testImmPredicate_I64` function.
   /// Note: `emitImmPredicateFnsImpl` can be used to do most of the work.
   virtual void emitI64ImmPredicateFns(raw_ostream &OS) = 0;
diff --git a/llvm/utils/TableGen/GlobalISelCombinerEmitter.cpp b/llvm/utils/TableGen/GlobalISelCombinerEmitter.cpp
index afaf050..f62b265 100644
--- a/llvm/utils/TableGen/GlobalISelCombinerEmitter.cpp
+++ b/llvm/utils/TableGen/GlobalISelCombinerEmitter.cpp
@@ -2414,6 +2414,7 @@ class GICombinerEmitter final : public GlobalISelMatchTableExecutorEmitter {
   void emitAdditionalImpl(raw_ostream &OS) override;
 
   void emitMIPredicateFns(raw_ostream &OS) override;
+  void emitLeafPredicateFns(raw_ostream &OS) override;
   void emitI64ImmPredicateFns(raw_ostream &OS) override;
   void emitAPFloatImmPredicateFns(raw_ostream &OS) override;
   void emitAPIntImmPredicateFns(raw_ostream &OS) override;
@@ -2581,6 +2582,12 @@ void GICombinerEmitter::emitMIPredicateFns(raw_ostream &OS) {
       [](const CXXPredicateCode *C) -> StringRef { return C->Code; });
 }
 
+void GICombinerEmitter::emitLeafPredicateFns(raw_ostream &OS) {
+  // Unused, but still needs to be called.
+  emitLeafPredicateFnsImpl<unsigned>(
+      OS, "", {}, [](unsigned) { return ""; }, [](unsigned) { return ""; });
+}
+
 void GICombinerEmitter::emitI64ImmPredicateFns(raw_ostream &OS) {
   // Unused, but still needs to be called.
   emitImmPredicateFnsImpl<unsigned>(
diff --git a/llvm/utils/TableGen/GlobalISelEmitter.cpp b/llvm/utils/TableGen/GlobalISelEmitter.cpp
index 55f60db..5b61d6e 100644
--- a/llvm/utils/TableGen/GlobalISelEmitter.cpp
+++ b/llvm/utils/TableGen/GlobalISelEmitter.cpp
@@ -321,6 +321,7 @@ public:
   void emitAdditionalImpl(raw_ostream &OS) override;
 
   void emitMIPredicateFns(raw_ostream &OS) override;
+  void emitLeafPredicateFns(raw_ostream &OS) override;
   void emitI64ImmPredicateFns(raw_ostream &OS) override;
   void emitAPFloatImmPredicateFns(raw_ostream &OS) override;
   void emitAPIntImmPredicateFns(raw_ostream &OS) override;
@@ -1110,8 +1111,16 @@ Error GlobalISelEmitter::importChildMatcher(
     return Error::success();
   }
 
-  if (SrcChild.hasAnyPredicate())
-    return failedImport("Src pattern child has unsupported predicate");
+  if (SrcChild.hasAnyPredicate()) {
+    for (const TreePredicateCall &Call : SrcChild.getPredicateCalls()) {
+      const TreePredicateFn &Predicate = Call.Fn;
+
+      if (!Predicate.hasGISelLeafPredicateCode())
+        return failedImport("Src pattern child has unsupported predicate");
+      OM.addPredicate<OperandLeafPredicateMatcher>(Predicate);
+    }
+    return Error::success();
+  }
 
   // Check for constant immediates.
   if (auto *ChildInt = dyn_cast<IntInit>(SrcChild.getLeafValue())) {
@@ -2293,6 +2302,26 @@ void GlobalISelEmitter::emitMIPredicateFns(raw_ostream &OS) {
       "PatFrag predicates.");
 }
 
+void GlobalISelEmitter::emitLeafPredicateFns(raw_ostream &OS) {
+  std::vector<const Record *> MatchedRecords;
+  llvm::copy_if(AllPatFrags, std::back_inserter(MatchedRecords),
+                [](const Record *R) {
+                  return (!R->getValueAsOptionalString("GISelLeafPredicateCode")
+                               .value_or(std::string())
+                               .empty());
+                });
+  emitLeafPredicateFnsImpl<const Record *>(
+      OS,
+      "  const auto &Operands = State.RecordedOperands;\n"
+      "  Register Reg = MO.getReg();\n"
+      "  (void)Operands;",
+      ArrayRef<const Record *>(MatchedRecords), &getPatFragPredicateEnumName,
+      [](const Record *R) {
+        return R->getValueAsString("GISelLeafPredicateCode");
+      },
+      "PatFrag predicates.");
+}
+
 void GlobalISelEmitter::emitI64ImmPredicateFns(raw_ostream &OS) {
   std::vector<const Record *> MatchedRecords;
   llvm::copy_if(AllPatFrags, std::back_inserter(MatchedRecords),