[llvm] [X86][GlobalIsel] add test for fabs isel (PR #142558)

[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=x86_64-- -mattr=+x87,-sse2,-sse | FileCheck %s --check-prefixes=X64
+; RUN: llc < %s -mtriple=x86_64-- -mattr=+x87,-sse2,-sse -fast-isel -fast-isel-abort=1 | FileCheck %s --check-prefixes=X64
+; RUN: llc < %s -mtriple=i686-- -mattr=+x87,-sse2,-sse | FileCheck %s --check-prefixes=X86
+; RUN: llc < %s -mtriple=i686-- -mattr=+x87,-sse2,-sse -fast-isel -fast-isel-abort=1 | FileCheck %s --check-prefixes=X86
+
+define x86_fp80 @test_x86_fp80_abs(x86_fp80 %arg) {
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mahesh-attarde wrote:

In presence of `-sse` and `-sse2`, SelectionDAG fails for float and double. llc panics with ` SSE register return with SSE disabled` for float and double.
https://godbolt.org/z/sMGqMYYbr


https://github.com/llvm/llvm-project/pull/142558