[llvm] Add Instruction selection support for x87 ld/st (PR #97016)

[Matt Arsenault via llvm-commits]

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+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mtriple=i686-- -mattr=+x87,-sse,-sse2 -global-isel | FileCheck %s --check-prefixes=CHECK-32,GISEL_X86
+; RUN: llc < %s -mtriple=x86_64-- -mattr=+x87,-sse,-sse2 -global-isel | FileCheck %s --check-prefixes=CHECK-64,GISEL_X64
+; RUN: llc < %s -mtriple=i686-- -mattr=+x87,-sse,-sse2 | FileCheck %s --check-prefixes=CHECK-32,SDAG_X86
+; RUN: llc < %s -mtriple=x86_64-- -mattr=+x87,-sse,-sse2 | FileCheck %s --check-prefixes=CHECK-64,SDAG_X64
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arsenm wrote:

I'm not sure it belongs in the top-level directory. Presumably this would be covered by an existing test there, in which case it would gain global-isel run lines. I don't think this should bother testing the fast-isel case (or the DAG case, but I could see why that one would be more useful to see whenever the output matches) 

https://github.com/llvm/llvm-project/pull/97016