[llvm] DAG: Gracefully diagnose missing FMA and ppcf128 expansion libcalls (PR #228094)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,82 @@
+; RUN: not llc -mtriple=x86_64-unknown-unknown -filetype=null %s 2>&1 | FileCheck %s
+
+; x86 expands ppc_fp128 but has no ppc_fp128 runtime library, so these
+; operations should diagnose a missing libcall rather than crash.
+
+; CHECK: error: no libcall available for fsqrt
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RKSimon wrote:

add test for libcall with different argument types - ldexp of something?

https://github.com/llvm/llvm-project/pull/228094