[llvm] [IR] Add a test for `f128` libm libcall lowering (NFC) (PR #148308)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,337 @@
+; Verify that fp128 intrinsics only lower to `long double` calls (e.g. sinl) on
+; platforms where 128 and `long double` have the same layout.Otherwise, lower
+; to f128 versions (e.g. sinf128).
+;
+; Targets include:
+; * aarch64 (long double == f128, should use ld syms)
+; * arm (long double == f64, should use f128 syms)
+; * s390x (long double == f128, should use ld syms, some hardware support)
+; * x86, x64 (80-bit long double, should use ld syms)
+; * gnu (has f128 symbols on all platforms so we can use those)
+; * musl (no f128 symbols available)
+; * Windows and MacOS (no f128 symbols, long double == f64)
+
+; FIXME(#44744): arm32, x86-{32,64} musl targets, MacOS, and Windows don't have
+; f128 long double. They should be passing with CHECK-F128 rather than
+; CHECK-USELD.
+
+; RUN: %if aarch64-registered-target %{ llc < %s -mtriple=aarch64-unknown-linux-gnu    -verify-machineinstrs | FileCheck %s --check-prefixes=CHECK-ALL,CHECK-USELD %}
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nikic wrote:

Please drop `-verify-machineinstrs` everywhere.

https://github.com/llvm/llvm-project/pull/148308