[llvm] [GlobalISel] Support physical register inputs in nested patterns (PR #121239)

[Sergei Barannikov via llvm-commits]

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@@ -1412,15 +1412,18 @@ Expected<BuildMIAction &> GlobalISelEmitter::createAndImportInstructionRenderer(
   action_iterator InsertPt = InsertPtOrError.get();
   BuildMIAction &DstMIBuilder = *static_cast<BuildMIAction *>(InsertPt->get());
 
-  for (auto PhysInput : InsnMatcher.getPhysRegInputs()) {
-    InsertPt = M.insertAction<BuildMIAction>(
-        InsertPt, M.allocateOutputInsnID(),
-        &Target.getInstruction(RK.getDef("COPY")));
-    BuildMIAction &CopyToPhysRegMIBuilder =
-        *static_cast<BuildMIAction *>(InsertPt->get());
-    CopyToPhysRegMIBuilder.addRenderer<AddRegisterRenderer>(
-        Target, PhysInput.first, true);
-    CopyToPhysRegMIBuilder.addRenderer<CopyPhysRegRenderer>(PhysInput.first);
+  for (auto PhysOp : M.physoperands()) {
+    auto &OpInsnMatcher = PhysOp.second->getInstructionMatcher();
+    for (auto PhysInput : OpInsnMatcher.getPhysRegInputs()) {
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s-barannikov wrote:

If there are more than one phys reg inputs, this loop nest will add them several times.
It looks like this map iterated in the inner loop is redundant, `physregoperands` returns all physreg inputs.


https://github.com/llvm/llvm-project/pull/121239