[llvm] [PowerPC] Handle CALL_RM like CALL for 32-bit ELF (PR #72758)

[Chen Zheng via llvm-commits]

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@@ -5475,7 +5475,8 @@ void PPCDAGToDAGISel::Select(SDNode *N) {
     // generate secure plt code for TLS symbols.
     getGlobalBaseReg();
   } break;
-  case PPCISD::CALL: {
+  case PPCISD::CALL:
+  case PPCISD::CALL_RM: {
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chenzheng1030 wrote:

Are your targeting this for SPE? SPE should have no floating point instructions? So round mode should not be a concern? For SPE, we may stop generate CALL_RM where it is generated. Note that CALL_RM performs worse than normal CALL even after instruction selection. They are selected to different instructions.

If for other PPC32 targets, the fix looks reasonable to me. 

https://github.com/llvm/llvm-project/pull/72758