[llvm] [X86][GlobalIsel] support G_FABS (PR #136718)

[Simon Pilgrim via llvm-commits]

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@@ -41,10 +65,30 @@ define double @test_double_abs(double %arg) {
 ;
 ; FASTISEL-X86-LABEL: test_double_abs:
 ; FASTISEL-X86:       # %bb.0:
+; FASTISEL-X86-NEXT:    pushl %ebp
+; FASTISEL-X86-NEXT:    .cfi_def_cfa_offset 8
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RKSimon wrote:

add nounwind to get rid of the cfi noise

https://github.com/llvm/llvm-project/pull/136718