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

[Evgenii Kudriashov 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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e-kud wrote:

@s-barannikov yes, thank you! I'll add this as a test as well.
I assumed that InsnMatcher is a must but we can just take keys from `PhysRegOperands` as only they are needed. And the duplication problem is solved completely as `PhysRegOperands` is a `DenseMap`. Only named phys registers are a problem but it looks like they are not supported yet. The test for them is commented out.

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