harec

commit 5dd2f47cc59173ff36e3cf323e64e35902c8285a
parent ab0bd2f1708829d387db797af79458717c86abc4
Author: Drew DeVault <sir@cmpwn.com>
Date:   Thu,  1 Apr 2021 13:06:47 -0400

Remove str => *const char cast

Diffstat:
M
rt/Makefile
 | 
1
+
M
rt/abort.ha
 | 
16
++++++++--------
M
rt/compile.ha
 | 
8
++++++--
A
rt/cstrings.ha
 | 
10
++++++++++
M
src/gen.c
 | 
8
++------
M
src/types.c
 | 
5
+----
M
tests/04-strings.ha
 | 
13
+------------

7 files changed, 29 insertions(+), 32 deletions(-)
diff --git a/rt/Makefile b/rt/Makefile
@@ -1,5 +1,6 @@
 libhart_srcs+=\
 	rt/abort.ha \
+	rt/cstrings.ha \
 	rt/compile.ha \
 	rt/ensure.ha \
 	rt/malloc.ha \
diff --git a/rt/abort.ha b/rt/abort.ha
@@ -1,8 +1,8 @@
 export @noreturn @symbol("rt.abort") fn _abort(msg: str) void = {
 	const prefix = "Abort: ";
-	write(2, prefix: *const char, len(prefix));
-	write(2, msg: *const char, len(msg));
-	write(2, "\n": *const char, 1);
+	write(2, constchar(prefix), len(prefix));
+	write(2, constchar(msg), len(msg));
+	write(2, constchar("\n"), 1);
 	kill(getpid(), SIGABRT);
 };
 
@@ -16,10 +16,10 @@ const reasons: [_]str = [
 export @noreturn fn abort_fixed(loc: str, i: int) void = {
 	const prefix = "Abort: ";
 	const sep = ": ";
-	write(2, prefix: *const char, len(prefix));
-	write(2, loc: *const char, len(loc));
-	write(2, sep: *const char, len(sep));
-	write(2, reasons[i]: *const char, len(reasons[i]));
-	write(2, "\n": *const char, 1);
+	write(2, constchar(prefix), len(prefix));
+	write(2, constchar(loc), len(loc));
+	write(2, constchar(sep), len(sep));
+	write(2, constchar(reasons[i]), len(reasons[i]));
+	write(2, constchar("\n"), 1);
 	kill(getpid(), SIGABRT);
 };
diff --git a/rt/compile.ha b/rt/compile.ha
@@ -12,14 +12,18 @@ export fn compile(src: const str) int = {
 		close(2);
 
 		const path = "./harec";
-		const argv: [_]nullable *const char = [path, "-", null];
+		const argv: [_]nullable *const char = [
+			constchar(path),
+			constchar("-"),
+			null
+		];
 		const envp: [_]nullable *const char = [null];
 		execve(path, &argv, &envp);
 		abort();
 	} else {
 		close(pipefd[0]);
 
-		const buf = src: *const char: *const [*]u8;
+		const buf = constchar(src): *const [*]u8;
 		for (let n = 0z; n < len(src)) {
 			let m = write(pipefd[1], &buf[n], len(src) - n);
 			assert(m > 0, "write(2) failed");
diff --git a/rt/cstrings.ha b/rt/cstrings.ha
@@ -0,0 +1,10 @@
+type string = struct {
+	data: nullable *[*]u8,
+	length: size,
+	capacity: size,
+};
+
+fn constchar(s: str) *const char = {
+	let s = &s: *string;
+	return s.data: *const char;
+};
diff --git a/src/gen.c b/src/gen.c
@@ -1305,12 +1305,8 @@ gen_expr_cast(struct gen_context *ctx,
 	struct qbe_value in = {0}, result = {0};
 	gen_temp(ctx, &result, qtype_for_type(ctx, to, false), "cast.out.%d");
 
-	// Special case: str -> *const char; slice -> ptr
-	if ((to->storage == STORAGE_POINTER
-			&& to->pointer.referent->storage == STORAGE_CHAR
-			&& from->storage == STORAGE_STRING)
-		|| (to->storage == STORAGE_POINTER
-			&& from->storage == STORAGE_SLICE)) {
+	// Special case: slice -> ptr
+	if (to->storage == STORAGE_POINTER && from->storage == STORAGE_SLICE) {
 		alloc_temp(ctx, &in, from, "cast.in.%d");
 		in.indirect = false;
 		gen_expression(ctx, expr->cast.value, &in);
diff --git a/src/types.c b/src/types.c
@@ -705,11 +705,8 @@ type_is_castable(const struct type *to, const struct type *from)
 			|| (to->storage == STORAGE_POINTER
 					&& to->pointer.referent->storage == STORAGE_ARRAY
 					&& from->storage == STORAGE_SLICE);
-	case STORAGE_STRING:
-		return to->storage == STORAGE_POINTER
-				&& to->pointer.referent->storage == STORAGE_CHAR
-				&& to->pointer.referent->flags & TYPE_CONST;
 	// Cannot be cast:
+	case STORAGE_STRING:
 	case STORAGE_BOOL:
 	case STORAGE_VOID:
 	case STORAGE_FUNCTION:
diff --git a/tests/04-strings.ha b/tests/04-strings.ha
@@ -11,16 +11,6 @@ fn measurements() void = {
 	assert(&x: uintptr: size % align == 0);
 };
 
-fn charptr() void = {
-	const x = "Hello!";
-	const y = x: *const char;
-	const z = y: *[*]u8;
-	const expected = ['H', 'e', 'l', 'l', 'o', '!'];
-	for (let i = 0z; i < len(expected); i += 1) {
-		assert(z[i] == expected[i]: u32: u8);
-	};
-};
-
 fn storage() void = {
 	const string = "こんにちは";
 	const ptr = &string: *struct {
@@ -50,7 +40,7 @@ fn storage() void = {
 
 fn concat() void = {
 	const s = "Hell" "o, " "wor" "ld!";
-	const t = s: *const char: *[*]u8;
+	const t = *(&s: **[*]u8);
 	const expected = [
 		'H', 'e', 'l', 'l', 'o', ',', ' ',
 		'w', 'o', 'r', 'l', 'd', '!',
@@ -69,7 +59,6 @@ fn equality() void = {
 
 export fn main() void = {
 	measurements();
-	charptr();
 	storage();
 	concat();
 	equality();