2 files changed, 51 insertions, 0 deletions
diff --git a/llvm/test/TableGen/GlobalISelEmitter-PR39045.td b/llvm/test/TableGen/GlobalISelEmitter-PR39045.td
new file mode 100644
index 00000000000..c5d7bd81ae6
--- /dev/null
+++ b/llvm/test/TableGen/GlobalISelEmitter-PR39045.td
@@ -0,0 +1,45 @@
+// RUN: llvm-tblgen -gen-global-isel -I %p/../../include %s -o %t
+// RUN: FileCheck %s < %t
+
+// Both predicates should be tested
+// CHECK-DAG: GIM_CheckCxxInsnPredicate, /*MI*/0, /*FnId*/GIPFP_MI_Predicate_pat_frag_b,
+// CHECK-DAG: GIM_CheckCxxInsnPredicate, /*MI*/0, /*FnId*/GIPFP_MI_Predicate_pat_frag_a,
+
+include "llvm/Target/Target.td"
+
+def MyTargetISA : InstrInfo;
+def MyTarget : Target { let InstructionSet = MyTargetISA; }
+
+
+def pat_frag_a : PatFrag <(ops node:$ptr), (load node:$ptr), [{}]> {
+   let PredicateCode = [{ return isInstA(MI); }];
+   let GISelPredicateCode = [{ return isInstA(MI); }];
+}
+
+def pat_frag_b : PatFrag <(ops node:$ptr), (load node:$ptr), [{}]> {
+   let PredicateCode = [{ return isInstB(MI); }];
+   let GISelPredicateCode = [{ return isInstB(MI); }];
+}
+
+def R0 : Register<"r0"> { let Namespace = "MyTarget"; }
+def GPR32 : RegisterClass<"MyTarget", [i32], 32, (add R0)>;
+
+def inst_a : Instruction {
+  let OutOperandList = (outs GPR32:$dst);
+  let InOperandList = (ins GPR32:$src);
+}
+def inst_b : Instruction {
+  let OutOperandList = (outs GPR32:$dst);
+  let InOperandList = (ins GPR32:$src);
+}
+
+def : Pat <
+  (pat_frag_a GPR32:$src),
+  (inst_a GPR32:$src)
+>;
+
+def : Pat <
+  (pat_frag_b GPR32:$src),
+  (inst_b GPR32:$src)
+>;
+
diff --git a/llvm/utils/TableGen/GlobalISelEmitter.cpp b/llvm/utils/TableGen/GlobalISelEmitter.cpp
index a02f31a8723..03e2f381d9c 100644
--- a/llvm/utils/TableGen/GlobalISelEmitter.cpp
+++ b/llvm/utils/TableGen/GlobalISelEmitter.cpp
@@ -1837,6 +1837,12 @@ public:
   static bool classof(const InstructionPredicateMatcher *P) {
     return P->getKind() == IPM_GenericPredicate;
   }
+  bool isIdentical(const PredicateMatcher &B) const override {
+    return InstructionPredicateMatcher::isIdentical(B) &&
+           Predicate ==
+               static_cast<const GenericInstructionPredicateMatcher &>(B)
+                   .Predicate;
+  }
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckCxxInsnPredicate")