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

[Malay Sanghi via llvm-commits]

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@@ -0,0 +1,221 @@
+; 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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MalaySanghi wrote:

I've added a run line for fast-isel but fallsback to selection dag for all the functions. It seems add/store of fp80 are not supported.

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