Commit fa9006f8d1aa95934f31d5bedfcd3949267c9e72 | zig

author	Andrew Kelley <andrew@ziglang.org> 2017-08-30 00:46:38-04:00
committer	Andrew Kelley <andrew@ziglang.org> 2017-08-30 00:46:38-04:00
log	fa9006f8d1aa95934f31d5bedfcd3949267c9e72
tree	7551d28d4ee45e3ae5c6ebe73dd6979abe2b55ac
parent	c2357830b4350a4685f867566afd79eaf2cb3c66

generic functions can access comptime args in align value

See #37

2 files changed, 36 insertions(+), 31 deletions(-)

src
- analyze.cpp
test
- cases
  - align.zig

src/analyze.cpp+27-31

 @@ -1061,13 +1061,31 @@ void init_fn_type_id(FnTypeId *fn_type_id, AstNode *proto_node, size_t param_cou
     fn_type_id->is_var_args = fn_proto->is_var_args;
 }
-static TypeTableEntry *analyze_fn_type(CodeGen *g, AstNode *proto_node, Scope *child_scope, uint32_t alignment) {
+static bool analyze_const_align(CodeGen *g, Scope *scope, AstNode *node, uint32_t *result) {
+    IrInstruction *align_result = analyze_const_value(g, scope, node, get_align_amt_type(g), nullptr);
+    if (type_is_invalid(align_result->value.type))
+        return false;
+    uint32_t align_bytes = bigint_as_unsigned(&align_result->value.data.x_bigint);
+    if (align_bytes == 0) {
+        add_node_error(g, node, buf_sprintf("alignment must be >= 1"));
+        return false;
+    }
+    if (!is_power_of_2(align_bytes)) {
+        add_node_error(g, node, buf_sprintf("alignment value %" PRIu32 " is not a power of 2", align_bytes));
+        return false;
+    }
+    *result = align_bytes;
+    return true;
+}
+static TypeTableEntry *analyze_fn_type(CodeGen *g, AstNode *proto_node, Scope *child_scope) {
     assert(proto_node->type == NodeTypeFnProto);
     AstNodeFnProto *fn_proto = &proto_node->data.fn_proto;
     FnTypeId fn_type_id = {0};
     init_fn_type_id(&fn_type_id, proto_node, proto_node->data.fn_proto.params.length);
-    fn_type_id.alignment = alignment;
     for (; fn_type_id.next_param_index < fn_type_id.param_count; fn_type_id.next_param_index += 1) {
         AstNode *param_node = fn_proto->params.at(fn_type_id.next_param_index);
 @@ -1156,6 +1174,12 @@ static TypeTableEntry *analyze_fn_type(CodeGen *g, AstNode *proto_node, Scope *c
         param_info->is_noalias = param_node->data.param_decl.is_noalias;
     }
+    if (fn_proto->align_expr != nullptr) {
+        if (!analyze_const_align(g, child_scope, fn_proto->align_expr, &fn_type_id.alignment)) {
+            return g->builtin_types.entry_invalid;
+        }
+    }
     fn_type_id.return_type = analyze_type_expr(g, child_scope, fn_proto->return_type);
     switch (fn_type_id.return_type->id) {
 @@ -2012,25 +2036,6 @@ TypeTableEntry *get_test_fn_type(CodeGen *g) {
     return g->test_fn_type;
 }
-static bool analyze_const_align(CodeGen *g, Scope *scope, AstNode *node, uint32_t *result) {
-    IrInstruction *align_result = analyze_const_value(g, scope, node, get_align_amt_type(g), nullptr);
-    if (type_is_invalid(align_result->value.type))
-        return false;
-    uint32_t align_bytes = bigint_as_unsigned(&align_result->value.data.x_bigint);
-    if (align_bytes == 0) {
-        add_node_error(g, node, buf_sprintf("alignment must be >= 1"));
-        return false;
-    }
-    if (!is_power_of_2(align_bytes)) {
-        add_node_error(g, node, buf_sprintf("alignment value %" PRIu32 " is not a power of 2", align_bytes));
-        return false;
-    }
-    *result = align_bytes;
-    return true;
-}
 static void resolve_decl_fn(CodeGen *g, TldFn *tld_fn) {
     ImportTableEntry *import = tld_fn->base.import;
     AstNode *source_node = tld_fn->base.source_node;
 @@ -2061,16 +2066,7 @@ static void resolve_decl_fn(CodeGen *g, TldFn *tld_fn) {
         Scope *child_scope = fn_table_entry->fndef_scope ? &fn_table_entry->fndef_scope->base : tld_fn->base.parent_scope;
-        uint32_t alignment = 0;
+        fn_table_entry->type_entry = analyze_fn_type(g, source_node, child_scope);
-        if (fn_proto->align_expr != nullptr) {
-            if (!analyze_const_align(g, child_scope, fn_proto->align_expr, &alignment)) {
-                fn_table_entry->type_entry = g->builtin_types.entry_invalid;
-                tld_fn->base.resolution = TldResolutionInvalid;
-                return;
-            }
-        }
-        fn_table_entry->type_entry = analyze_fn_type(g, source_node, child_scope, alignment);
         if (fn_table_entry->type_entry->id == TypeTableEntryIdInvalid) {
             tld_fn->base.resolution = TldResolutionInvalid;

test/cases/align.zig+9

...	@@ -127,3 +127,12 @@ fn fnExpects4(ptr: fn()align 4 -> i32) -> i32 {	...	@@ -127,3 +127,12 @@ fn fnExpects4(ptr: fn()align 4 -> i32) -> i32 {
127	ptr()	127	ptr()
128	}	128	}
129	fn simple4() align 4 -> i32 { 0x19 }	129	fn simple4() align 4 -> i32 { 0x19 }
		130
		131
		132	test "generic function with align param" {
		133	assert(whyWouldYouEverDoThis(1) == 0x1);
		134	assert(whyWouldYouEverDoThis(4) == 0x1);
		135	assert(whyWouldYouEverDoThis(8) == 0x1);
		136	}
		137
		138	fn whyWouldYouEverDoThis(comptime align_bytes: u8) align align_bytes -> u8 { 0x1 }