From abf40caeb7d85d8fc842fe82215b19902b749481 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alex=20R=C3=B8nne=20Petersen?= <alex@alexrp.com>
Date: Mon, 20 Oct 2025 18:37:13 +0200
Subject: [PATCH] std.builtin: add CallingConvention.msp430_interrupt

Supported by LLVM and CBE.
---
 lib/std/Target.zig   | 1 +
 lib/std/builtin.zig  | 1 +
 src/Sema.zig         | 3 +++
 src/Zcu.zig          | 1 +
 src/codegen/c.zig    | 1 +
 src/codegen/llvm.zig | 1 +
 src/link/Dwarf.zig   | 1 +
 7 files changed, 9 insertions(+)

diff --git a/lib/std/Target.zig b/lib/std/Target.zig
index b99e2b366e..257113f477 100644
--- a/lib/std/Target.zig
+++ b/lib/std/Target.zig
@@ -1907,6 +1907,7 @@ pub const Cpu = struct {
                 => &.{ .microblaze, .microblazeel },
 
                 .msp430_eabi,
+                .msp430_interrupt,
                 => &.{.msp430},
 
                 .or1k_sysv,
diff --git a/lib/std/builtin.zig b/lib/std/builtin.zig
index 6feacbc8c8..84b228d685 100644
--- a/lib/std/builtin.zig
+++ b/lib/std/builtin.zig
@@ -326,6 +326,7 @@ pub const CallingConvention = union(enum(u8)) {
 
     /// The standard `msp430` calling convention.
     msp430_eabi: CommonOptions,
+    msp430_interrupt: CommonOptions,
 
     /// The standard `or1k` calling convention.
     or1k_sysv: CommonOptions,
diff --git a/src/Sema.zig b/src/Sema.zig
index 47b5339222..62e6942a5b 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -9137,6 +9137,7 @@ fn callConvIsCallable(cc: std.builtin.CallingConvention.Tag) bool {
         .m68k_interrupt,
         .mips_interrupt,
         .mips64_interrupt,
+        .msp430_interrupt,
         .riscv32_interrupt,
         .riscv64_interrupt,
         .x86_interrupt,
@@ -9301,6 +9302,7 @@ fn funcCommon(
             .avr_interrupt,
             .csky_interrupt,
             .m68k_interrupt,
+            .msp430_interrupt,
             .avr_signal,
             => return sema.fail(block, param_src, "parameters are not allowed with '{s}' calling convention", .{@tagName(cc)}),
             else => {},
@@ -9528,6 +9530,7 @@ fn finishFunc(
         .avr_interrupt,
         .csky_interrupt,
         .m68k_interrupt,
+        .msp430_interrupt,
         .avr_signal,
         => if (return_type.zigTypeTag(zcu) != .void and return_type.zigTypeTag(zcu) != .noreturn) {
             return sema.fail(block, ret_ty_src, "function with calling convention '{s}' must return 'void' or 'noreturn'", .{@tagName(cc_resolved)});
diff --git a/src/Zcu.zig b/src/Zcu.zig
index 6fa200561c..9839db6659 100644
--- a/src/Zcu.zig
+++ b/src/Zcu.zig
@@ -4426,6 +4426,7 @@ pub fn callconvSupported(zcu: *Zcu, cc: std.builtin.CallingConvention) union(enu
                 .riscv32_ilp32_v,
                 .m68k_rtd,
                 .m68k_interrupt,
+                .msp430_interrupt,
                 => |opts| opts.incoming_stack_alignment == null,
 
                 .arm_aapcs_vfp,
diff --git a/src/codegen/c.zig b/src/codegen/c.zig
index cf0519e1f1..a47d031520 100644
--- a/src/codegen/c.zig
+++ b/src/codegen/c.zig
@@ -8113,6 +8113,7 @@ fn toCallingConvention(cc: std.builtin.CallingConvention, zcu: *Zcu) ?[]const u8
         .avr_interrupt,
         .csky_interrupt,
         .m68k_interrupt,
+        .msp430_interrupt,
         .x86_interrupt,
         .x86_64_interrupt,
         => "interrupt",
diff --git a/src/codegen/llvm.zig b/src/codegen/llvm.zig
index 3b3febf27e..9d23178887 100644
--- a/src/codegen/llvm.zig
+++ b/src/codegen/llvm.zig
@@ -11900,6 +11900,7 @@ fn toLlvmCallConvTag(cc_tag: std.builtin.CallingConvention.Tag, target: *const s
         .avr_interrupt => .avr_intrcc,
         .m68k_rtd => .m68k_rtdcc,
         .m68k_interrupt => .m68k_intrcc,
+        .msp430_interrupt => .msp430_intrcc,
         .amdgcn_kernel => .amdgpu_kernel,
         .amdgcn_cs => .amdgpu_cs,
         .nvptx_device => .ptx_device,
diff --git a/src/link/Dwarf.zig b/src/link/Dwarf.zig
index 2ecac73c1c..cc440905f0 100644
--- a/src/link/Dwarf.zig
+++ b/src/link/Dwarf.zig
@@ -3925,6 +3925,7 @@ fn updateLazyType(
                     .avr_interrupt,
                     .csky_interrupt,
                     .m68k_interrupt,
+                    .msp430_interrupt,
                     => .normal,
 
                     else => .nocall,