cbe,translate-c: support more callconvs

There are several more that we could support here, but I didn't feel
like going down the rabbit-hole of figuring them out. In particular,
some of the Clang enum fields aren't specific enough for us, so we'll
have to switch on the target to figure out how to translate-c them. That
can be a future enhancement.

lib/compiler/aro_translate_c/ast.zig

@@ -560,6 +560,7 @@ pub const Payload = struct {
         pub const CallingConvention = enum {
             c,
             x86_64_sysv,
+            x86_64_win,
             x86_stdcall,
             x86_fastcall,
             x86_thiscall,
@@ -567,6 +568,7 @@ pub const Payload = struct {
             aarch64_vfabi,
             arm_aapcs,
             arm_aapcs_vfp,
+            m68k_rtd,
         };
     };
 
@@ -2834,6 +2836,7 @@ fn renderFunc(c: *Context, node: Node) !NodeIndex {
                 });
             },
             .x86_64_sysv,
+            .x86_64_win,
             .x86_stdcall,
             .x86_fastcall,
             .x86_thiscall,
@@ -2841,6 +2844,7 @@ fn renderFunc(c: *Context, node: Node) !NodeIndex {
             .aarch64_vfabi,
             .arm_aapcs,
             .arm_aapcs_vfp,
+            .m68k_rtd,
             => cc_node: {
                 // .{ .foo = .{} }
                 _ = try c.addToken(.period, ".");

src/Zcu.zig

@@ -3568,12 +3568,27 @@ pub fn callconvSupported(zcu: *Zcu, cc: std.builtin.CallingConvention) union(enu
                 }
             }
             break :ok switch (cc) {
+                .x86_64_sysv,
+                .x86_64_win,
                 .x86_64_vectorcall,
+                .x86_64_regcall_v3_sysv,
+                .x86_64_regcall_v4_win,
                 .x86_fastcall,
                 .x86_thiscall,
                 .x86_vectorcall,
+                .x86_regcall_v3,
+                .x86_regcall_v4_win,
+                .aarch64_vfabi,
+                .aarch64_vfabi_sve,
+                .arm_aapcs,
+                .arm_aapcs_vfp,
+                .riscv64_lp64_v,
+                .riscv32_ilp32_v,
+                .m68k_rtd,
                 => |opts| opts.incoming_stack_alignment == null,
 
+                .x86_sysv,
+                .x86_win,
                 .x86_stdcall,
                 => |opts| opts.incoming_stack_alignment == null and opts.register_params == 0,
 

src/codegen/c.zig

@@ -7605,16 +7605,38 @@ fn writeMemoryOrder(w: anytype, order: std.builtin.AtomicOrder) !void {
 }
 
 fn toCallingConvention(cc: std.builtin.CallingConvention, zcu: *Zcu) ?[]const u8 {
+    if (zcu.getTarget().cCallingConvention()) |ccc| {
+        if (cc.eql(ccc)) {
+            return null;
+        }
+    }
     return switch (cc) {
         .auto, .naked => null,
+
+        .x86_64_sysv, .x86_sysv => "sysv_abi",
+        .x86_64_win, .x86_win => "ms_abi",
         .x86_stdcall => "stdcall",
         .x86_fastcall => "fastcall",
-        .x86_vectorcall, .x86_64_vectorcall => "vectorcall",
-        else => {
-            // `Zcu.callconvSupported` means this must be the C callconv.
-            assert(cc.eql(zcu.getTarget().cCallingConvention().?));
-            return null;
-        },
+        .x86_thiscall => "thiscall",
+
+        .x86_vectorcall,
+        .x86_64_vectorcall,
+        => "vectorcall",
+
+        .x86_64_regcall_v3_sysv,
+        .x86_64_regcall_v4_win,
+        .x86_regcall_v3,
+        .x86_regcall_v4_win,
+        => "regcall",
+
+        .aarch64_vfabi => "aarch64_vector_pcs",
+        .aarch64_vfabi_sve => "aarch64_sve_pcs",
+        .arm_aapcs => "pcs(\"aapcs\")",
+        .arm_aapcs_vfp => "pcs(\"aapcs-vfp\")",
+        .riscv64_lp64_v, .riscv32_ilp32_v => "riscv_vector_cc",
+        .m68k_rtd => "m68k_rtd",
+
+        else => unreachable, // `Zcu.callconvSupported`
     };
 }
 

src/translate_c.zig

@@ -5005,6 +5005,7 @@ fn transCC(
     return switch (clang_cc) {
         .C => .c,
         .X86_64SysV => .x86_64_sysv,
+        .Win64 => .x86_64_win,
         .X86StdCall => .x86_stdcall,
         .X86FastCall => .x86_fastcall,
         .X86ThisCall => .x86_thiscall,
@@ -5012,6 +5013,7 @@ fn transCC(
         .AArch64VectorCall => .aarch64_vfabi,
         .AAPCS => .arm_aapcs,
         .AAPCS_VFP => .arm_aapcs_vfp,
+        .M68kRTD => .m68k_rtd,
         else => return fail(
             c,
             error.UnsupportedType,