From fe6b09397c03f621f0be27287d9c5934d70f3fd2 Mon Sep 17 00:00:00 2001
From: Sebastian Neubauer <sebastian.neubauer@amd.com>
Date: Thu, 26 Dec 2024 06:01:14 +0100
Subject: [PATCH] Disable f128 for amdgpu (#737)
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`compiler_builtins` fails to compile to amdgpu if f128 is enabled.
The reason seems to be that compiler_builtins uses libcalls in the
implementation. I’m not really familiar with what libcalls are, but the
LLVM amdgpu backend explicitly does not support them.

Error message:
```
LLVM ERROR: unsupported libcall legalization
```
---
 configure.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/configure.rs b/configure.rs
index 0a0bd503..e20c717e 100644
--- a/configure.rs
+++ b/configure.rs
@@ -79,6 +79,8 @@ pub fn configure_f16_f128(target: &Target) {
     };
 
     let f128_enabled = match target.arch.as_str() {
+        // Unsupported (libcall is not supported) <https://github.com/llvm/llvm-project/issues/121122>
+        "amdgpu" => false,
         // Unsupported <https://github.com/llvm/llvm-project/issues/94434>
         "arm64ec" => false,
         // Selection failure <https://github.com/llvm/llvm-project/issues/96432>