Commit 874c63f89cb6174d2dba32f4d08c140b5eed6744 | zig

author	Evan Haas <evan@lagerdata.com> 2021-03-06 09:17:17-08:00
committer	Veikka Tuominen <git@vexu.eu> 2021-03-07 14:53:33+02:00
log	874c63f89cb6174d2dba32f4d08c140b5eed6744
tree	d4f68a819de0b2545bd3a8d8156112c68e0358ad
parent	a7c0234eee97c11b1dd6879a3cf313ac9a7bdbd9

translate-c: translate align attribute for block scoped variables

2 files changed, 18 insertions(+), 29 deletions(-)

src
- translate_c.zig
test
- translate_c.zig

src/translate_c.zig+12-29

 @@ -671,15 +671,6 @@ fn visitVarDecl(c: *Context, var_decl: *const clang.VarDecl, mangled_name: ?[]co
         break :blk null;
     };
-    const alignment = blk: {
-        const alignment = var_decl.getAlignedAttribute(c.clang_context);
-        if (alignment != 0) {
-            // Clang reports the alignment in bits
-            break :blk alignment / 8;
-        }
-        break :blk null;
-    };
     const node = try Tag.var_decl.create(c.arena, .{
         .is_pub = is_pub,
         .is_const = is_const,
 @@ -687,7 +678,7 @@ fn visitVarDecl(c: *Context, var_decl: *const clang.VarDecl, mangled_name: ?[]co
         .is_export = is_export,
         .is_threadlocal = is_threadlocal,
         .linksection_string = linksection_string,
-        .alignment = alignment,
+        .alignment = zigAlignment(var_decl.getAlignedAttribute(c.clang_context)),
         .name = checked_name,
         .type = type_node,
         .init = init_node,
 @@ -833,14 +824,7 @@ fn transRecordDecl(c: *Context, scope: *Scope, record_decl: *const clang.RecordD
                 else => |e| return e,
             };
-            const alignment = blk_2: {
+            const alignment = zigAlignment(field_decl.getAlignedAttribute(c.clang_context));
-                const alignment = field_decl.getAlignedAttribute(c.clang_context);
-                if (alignment != 0) {
-                    // Clang reports the alignment in bits
-                    break :blk_2 alignment / 8;
-                }
-                break :blk_2 null;
-            };
             if (is_anon) {
                 try c.decl_table.putNoClobber(c.gpa, @ptrToInt(field_decl.getCanonicalDecl()), field_name);
 @@ -1373,6 +1357,13 @@ fn transCStyleCastExprClass(
     return maybeSuppressResult(c, scope, result_used, cast_node);
 }
+/// Clang reports the alignment in bits, we use bytes
+/// Clang uses 0 for "no alignment specified", we use null
+fn zigAlignment(bit_alignment: c_uint) ?c_uint {
+    if (bit_alignment == 0) return null;
+    return bit_alignment / 8;
+}
 fn transDeclStmtOne(
     c: *Context,
     scope: *Scope,
 @@ -1412,6 +1403,7 @@ fn transDeclStmtOne(
             if (!qualTypeIsBoolean(qual_type) and isBoolRes(init_node)) {
                 init_node = try Tag.bool_to_int.create(c.arena, init_node);
             }
             const node = try Tag.var_decl.create(c.arena, .{
                 .is_pub = false,
                 .is_const = is_const,
 @@ -1419,7 +1411,7 @@ fn transDeclStmtOne(
                 .is_export = false,
                 .is_threadlocal = false,
                 .linksection_string = null,
-                .alignment = null,
+                .alignment = zigAlignment(var_decl.getAlignedAttribute(c.clang_context)),
                 .name = mangled_name,
                 .type = type_node,
                 .init = init_node,
 @@ -4111,16 +4103,7 @@ fn finishTransFnProto(
         break :blk null;
     };
-    const alignment = blk: {
+    const alignment = if (fn_decl) |decl| zigAlignment(decl.getAlignedAttribute(c.clang_context)) else null;
-        if (fn_decl) |decl| {
-            const alignment = decl.getAlignedAttribute(c.clang_context);
-            if (alignment != 0) {
-                // Clang reports the alignment in bits
-                break :blk alignment / 8;
-            }
-        }
-        break :blk null;
-    };
     const explicit_callconv = if ((is_export or is_extern) and cc == .C) null else cc;

test/translate_c.zig+6

 @@ -643,9 +643,15 @@ pub fn addCases(cases: *tests.TranslateCContext) void {
         \\extern char my_array[16];
         \\__attribute__ ((aligned(128)))
         \\void my_fn(void) { }
+        \\void other_fn(void) {
+        \\    char ARR[16] __attribute__ ((aligned (16)));
+        \\}
     , &[_][]const u8{
         \\pub extern var my_array: [16]u8 align(128);
         \\pub export fn my_fn() align(128) void {}
+        \\pub export fn other_fn() void {
+        \\    var ARR: [16]u8 align(16) = undefined;
+        \\}
     });
     cases.add("linksection() attribute",