[llvm] [ARM] Fix calling convention for __fp16 with big-endian (PR #126741)

[Oliver Stannard via llvm-commits]

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@@ -0,0 +1,288 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=armv8m.main-none-eabi   < %s -frame-pointer=none -mattr=+fp-armv8d16 | FileCheck %s --check-prefix=LE
+; RUN: llc -mtriple=armebv8m.main-none-eabi < %s -frame-pointer=none -mattr=+fp-armv8d16 | FileCheck %s --check-prefix=BE
+; RUN: llc -mtriple=armv8m.main-none-eabi   < %s -frame-pointer=none -mattr=+fp-armv8d16,+fullfp16 | FileCheck %s --check-prefix=LE-FP16
+; RUN: llc -mtriple=armebv8m.main-none-eabi < %s -frame-pointer=none -mattr=+fp-armv8d16,+fullfp16 | FileCheck %s --check-prefix=BE-FP16
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ostannard wrote:

Done, there are a few cases where we don't fall back, but do still generate correct code.

https://github.com/llvm/llvm-project/pull/126741