[llvm] [AArch64][CodeGen] Fix crash when fptrunc returns fp16 with +nofp attr (PR #81724)

[Nashe Mncube via llvm-commits]

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@@ -0,0 +1,20 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -mtriple=aarch64 -mattr=-fp-armv8 -o - %s | FileCheck %s
+
+define half @f2h(float %a) {
+; CHECK-LABEL: f2h:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    str x30, [sp, #-16]! // 8-byte Folded Spill
+; CHECK-NEXT:    .cfi_def_cfa_offset 16
+; CHECK-NEXT:    .cfi_offset w30, -16
+; CHECK-NEXT:    bl __gnu_f2h_ieee
+; CHECK-NEXT:    and w0, w0, #0xffff
+; CHECK-NEXT:    bl __gnu_h2f_ieee
+; CHECK-NEXT:    bl __gnu_f2h_ieee
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nasherm wrote:

This seems to have fixed things! The generated assembly is terser now.

https://github.com/llvm/llvm-project/pull/81724