rustc_codegen_llvm: update alignment for double on AIX

This was recently fixed upstream in LLVM, so we update our default
layout to match.

@rustbot label: +llvm-main

Author: durin42

compiler/rustc_codegen_llvm/src/context.rs

@@ -202,6 +202,10 @@ pub(crate) unsafe fn create_module<'ll>(
             // LLVM 22 updated the NVPTX layout to indicate 256-bit vector load/store: https://github.com/llvm/llvm-project/pull/155198
             target_data_layout = target_data_layout.replace("-i256:256", "");
         }
+        if sess.target.arch == Arch::PowerPC64 {
+            // LLVM 22 updated the ABI alignment for double on AIX: https://github.com/llvm/llvm-project/pull/144673
+            target_data_layout = target_data_layout.replace("64-f64:32:", "");
+        }
     }
 
     // Ensure the data-layout values hardcoded remain the defaults.

compiler/rustc_target/src/spec/targets/powerpc64_ibm_aix.rs

@@ -17,7 +17,8 @@ pub(crate) fn target() -> Target {
             std: None, // ?
         },
         pointer_width: 64,
-        data_layout: "E-m:a-Fi64-i64:64-i128:128-n32:64-S128-v256:256:256-v512:512:512".into(),
+        data_layout: "E-m:a-Fi64-i64:64-i128:128-n32:64-f64:32:64-S128-v256:256:256-v512:512:512"
+            .into(),
         arch: Arch::PowerPC64,
         options: base,
     }