Adjust LoongArch64 data layouts for LLVM update

The data layout was changed in LLVM 19: llvm/llvm-project#93814

Author: zmodem

compiler/rustc_codegen_llvm/src/context.rs

@@ -142,6 +142,14 @@ pub unsafe fn create_module<'ll>(
         }
     }
 
+    if llvm_version < (19, 0, 0) {
+        if sess.target.arch == "loongarch64" {
+            // LLVM 19 updates the LoongArch64 data layout.
+            // See https://github.com/llvm/llvm-project/pull/93814
+            target_data_layout = target_data_layout.replace("-n32:64", "-n64");
+        }
+    }
+
     // Ensure the data-layout values hardcoded remain the defaults.
     {
         let tm = crate::back::write::create_informational_target_machine(tcx.sess);

compiler/rustc_target/src/spec/targets/loongarch64_unknown_linux_gnu.rs

@@ -10,7 +10,7 @@ pub fn target() -> Target {
             std: None,
         },
         pointer_width: 64,
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         arch: "loongarch64".into(),
         options: TargetOptions {
             cpu: "generic".into(),

compiler/rustc_target/src/spec/targets/loongarch64_unknown_linux_musl.rs

@@ -10,7 +10,7 @@ pub fn target() -> Target {
             std: None,
         },
         pointer_width: 64,
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         arch: "loongarch64".into(),
         options: TargetOptions {
             cpu: "generic".into(),

compiler/rustc_target/src/spec/targets/loongarch64_unknown_none.rs

@@ -11,7 +11,7 @@ pub fn target() -> Target {
             std: None,
         },
         pointer_width: 64,
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         arch: "loongarch64".into(),
         options: TargetOptions {
             cpu: "generic".into(),

compiler/rustc_target/src/spec/targets/loongarch64_unknown_none_softfloat.rs

@@ -11,7 +11,7 @@ pub fn target() -> Target {
             std: None,
         },
         pointer_width: 64,
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         arch: "loongarch64".into(),
         options: TargetOptions {
             cpu: "generic".into(),