[llvm] [GlobalISel][TableGen] MIR Pattern Variadics (PR #100563)

[Pierre van Houtryve via llvm-commits]

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@@ -28,19 +28,48 @@ def InstTest3 : GICombineRule<
   (match (G_UNMERGE_VALUES $a, $b, $c, $d)),
   (apply [{ APPLY }])>;
 
+def VariadicTypeTestCxx : GICombineRule<
+  (defs root:$a),
+  (match (G_BUILD_VECTOR $a, GIVariadic<2, 4>:$b)),
+  (apply [{ ${b} }])>;
+
+def VariadicTypeTestReuse : GICombineRule<
+  (defs root:$a),
+  (match (G_BUILD_VECTOR $a, $c, GIVariadic<2, 4>:$b)),
+  (apply (G_MERGE_VALUES $a, $b, $c))>;
+
 def MyCombiner: GICombiner<"GenMyCombiner", [
   InstTest0,
   InstTest1,
   InstTest2,
-  InstTest3
+  InstTest3,
+  VariadicTypeTestCxx,
+  VariadicTypeTestReuse
 ]>;
 
+// CHECK:     bool GenMyCombiner::runCustomAction(unsigned ApplyID, const MatcherState &State, NewMIVector &OutMIs) const {
+// CHECK-NEXT:   Helper.getBuilder().setInstrAndDebugLoc(*State.MIs[0]);
+// CHECK-NEXT:   switch(ApplyID) {
+// CHECK-NEXT:   case GICXXCustomAction_GICombiner0:{
+// CHECK-NEXT:     // Apply Patterns
+// CHECK-NEXT:     APPLY
+// CHECK-NEXT:     return true;
+// CHECK-NEXT:   }
+// CHECK-NEXT:   case GICXXCustomAction_GICombiner1:{
+// CHECK-NEXT:     // Apply Patterns
+// CHECK-NEXT:     getRemainingOperands(*State.MIs[0], 1)
+// CHECK-NEXT:     return true;
+// CHECK-NEXT:   }
+// CHECK-NEXT:   }
+// CHECK-NEXT:   llvm_unreachable("Unknown Apply Action");
+// CHECK-NEXT: }
+
 // CHECK:      const uint8_t *GenMyCombiner::getMatchTable() const {
 // CHECK-NEXT:   constexpr static uint8_t MatchTable0[] = {
-// CHECK-NEXT:     GIM_SwitchOpcode, /*MI*/0, /*[*/GIMT_Encode2([[#LOWER:]]), GIMT_Encode2([[#UPPER:]]), /*)*//*default:*//*Label 2*/ GIMT_Encode4([[#DEFAULT:]]),
+// CHECK-NEXT:     GIM_SwitchOpcode, /*MI*/0, /*[*/GIMT_Encode2(70), GIMT_Encode2(74), /*)*//*default:*//*Label 2*/ GIMT_Encode4(127),
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Pierre-vh wrote:

There is no reason, I just forgot that those tests were changed to use regexes and I generally update them by copy-pasting the output of tblgen. I will make a patch to fix it.

https://github.com/llvm/llvm-project/pull/100563