[llvm] X86: Fix asserting on bfloat argument/return without sse2 (PR #93146)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,1441 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=i386-linux-gnu < %s | FileCheck -check-prefixes=CHECK,NOSSE %s
+; RUN: llc -mtriple=i386-linux-gnu -mattr=+sse < %s | FileCheck -check-prefixes=CHECK,SSE %s
+
+; Make sure no assert without SSE2 and bfloat. Issue 92899
+
+define bfloat @return_arg_bf16(bfloat %x) {
+; CHECK-LABEL: return_arg_bf16:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    flds {{[0-9]+}}(%esp)
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arsenm wrote:

The default logic is to legalize half to i16, and bfloat to float:

https://github.com/llvm/llvm-project/blob/335e00faaf74f3f7463b32a415d39af0973f521f/llvm/lib/CodeGen/TargetLoweringBase.cpp#L1529



https://github.com/llvm/llvm-project/pull/93146