llvm: Match aarch64 data layout to new LLVM layout

LLVM has added 3 new address spaces to support special Windows use
cases. These shouldn't trouble us for now, but LLVM requires matching
data layouts.

See llvm/llvm-project#111879 for details

Author: maurer

compiler/rustc_codegen_llvm/src/context.rs

@@ -138,6 +138,16 @@ pub(crate) unsafe fn create_module<'ll>(
         }
     }
 
+    if llvm_version < (20, 0, 0) {
+        if sess.target.arch == "aarch64" || sess.target.arch.starts_with("arm64") {
+            // LLVM 20 defines three additional address spaces for alternate
+            // pointer kinds used in Windows.
+            // See https://github.com/llvm/llvm-project/pull/111879
+            target_data_layout =
+                target_data_layout.replace("-p270:32:32-p271:32:32-p272:64:64", "");
+        }
+    }
+
     // Ensure the data-layout values hardcoded remain the defaults.
     {
         let tm = crate::back::write::create_informational_target_machine(tcx.sess, false);

compiler/rustc_target/src/spec/targets/aarch64_apple_darwin.rs

@@ -12,7 +12,8 @@ pub(crate) fn target() -> Target {
             std: Some(true),
         },
         pointer_width: 64,
-        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+            .into(),
         arch,
         options: TargetOptions {
             mcount: "\u{1}mcount".into(),

compiler/rustc_target/src/spec/targets/aarch64_apple_ios.rs

@@ -12,7 +12,8 @@ pub(crate) fn target() -> Target {
             std: Some(true),
         },
         pointer_width: 64,
-        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+            .into(),
         arch,
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".into(),

compiler/rustc_target/src/spec/targets/aarch64_apple_ios_macabi.rs

@@ -12,7 +12,8 @@ pub(crate) fn target() -> Target {
             std: Some(true),
         },
         pointer_width: 64,
-        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+            .into(),
         arch,
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a12".into(),

compiler/rustc_target/src/spec/targets/aarch64_apple_ios_sim.rs

@@ -12,7 +12,8 @@ pub(crate) fn target() -> Target {
             std: Some(true),
         },
         pointer_width: 64,
-        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+            .into(),
         arch,
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".into(),

compiler/rustc_target/src/spec/targets/aarch64_apple_tvos.rs

@@ -12,7 +12,8 @@ pub(crate) fn target() -> Target {
             std: Some(true),
         },
         pointer_width: 64,
-        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+            .into(),
         arch,
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".into(),

compiler/rustc_target/src/spec/targets/aarch64_apple_tvos_sim.rs

@@ -12,7 +12,8 @@ pub(crate) fn target() -> Target {
             std: Some(true),
         },
         pointer_width: 64,
-        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+            .into(),
         arch,
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".into(),

compiler/rustc_target/src/spec/targets/aarch64_apple_visionos.rs

@@ -12,7 +12,8 @@ pub(crate) fn target() -> Target {
             std: Some(false),
         },
         pointer_width: 64,
-        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+            .into(),
         arch,
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a16".into(),

compiler/rustc_target/src/spec/targets/aarch64_apple_visionos_sim.rs

@@ -12,7 +12,8 @@ pub(crate) fn target() -> Target {
             std: Some(false),
         },
         pointer_width: 64,
-        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+            .into(),
         arch,
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a16".into(),

compiler/rustc_target/src/spec/targets/aarch64_apple_watchos.rs

@@ -12,7 +12,8 @@ pub(crate) fn target() -> Target {
             std: Some(true),
         },
         pointer_width: 64,
-        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+            .into(),
         arch,
         options: TargetOptions {
             features: "+v8a,+neon,+fp-armv8,+apple-a7".into(),