Commit 91dba79c48f0a309e014062f2fe311a5c46b1084 | zig

author	Luuk de Gram <luuk@degram.dev> 2022-08-26 21:01:05+02:00
committer	Luuk de Gram <luuk@degram.dev> 2022-08-26 21:01:05+02:00
log	91dba79c48f0a309e014062f2fe311a5c46b1084
tree	bc869dd10ccb9bce56136e238cb4dfd1d9032ff5
parent	8bcb962ada2ea5cfeeff303e1063937ee13af6ad
signature	Commit is signed but in an unrecognized format.

wasm: fix abi size of c_longdouble

According to https://github.com/WebAssembly/tool-conventions/blob/main/BasicCABI.md
the size of c's long double is 16 bytes for Wasm, rather than 8 bytes
which was the value previously in the compiler. This ensures
we not only pass the correct value, but also creates the correct
function signature needed to pass the Wasm validator.

This also adds an additional test case in c_abi tests.

3 files changed, 15 insertions(+), 0 deletions(-)

src
- type.zig
test
- c_abi
  - cfuncs.c
  - main.zig

src/type.zig+4

...	...	@@ -6592,6 +6592,8 @@ pub const CType = enum {
6592	6592	.powerpcle,
6593	6593	.powerpc64,
6594	6594	.powerpc64le,
	6595	.wasm32,
	6596	.wasm64,
6595	6597	=> return 128,
6596	6598
6597	6599	else => return 64,
...	...	@@ -6640,6 +6642,8 @@ pub const CType = enum {
6640	6642	.powerpcle,
6641	6643	.powerpc64,
6642	6644	.powerpc64le,
	6645	.wasm32,
	6646	.wasm64,
6643	6647	=> return 128,
6644	6648
6645	6649	else => return 64,

test/c_abi/cfuncs.c+6

...	...	@@ -33,6 +33,7 @@ void zig_five_integers(int32_t, int32_t, int32_t, int32_t, int32_t);
33	33
34	34	void zig_f32(float);
35	35	void zig_f64(double);
	36	void zig_longdouble(long double);
36	37	void zig_five_floats(float, float, float, float, float);
37	38
38	39	bool zig_ret_bool();
...	...	@@ -157,6 +158,7 @@ void run_c_tests(void) {
157	158
158	159	zig_f32(12.34f);
159	160	zig_f64(56.78);
	161	zig_longdouble(12.34l);
160	162	zig_five_floats(1.0f, 2.0f, 3.0f, 4.0f, 5.0f);
161	163
162	164	zig_ptr((void*)0xdeadbeefL);
...	...	@@ -271,6 +273,10 @@ void c_f64(double x) {
271	273	assert_or_panic(x == 56.78);
272	274	}
273	275
	276	void c_long_double(long double x) {
	277	assert_or_panic(x == 12.34l);
	278	}
	279
274	280	void c_ptr(void *x) {
275	281	assert_or_panic(x == (void*)0xdeadbeefL);
276	282	}

test/c_abi/main.zig+5

...	...	@@ -89,6 +89,7 @@ export fn zig_struct_u128(a: U128) void {
89	89
90	90	extern fn c_f32(f32) void;
91	91	extern fn c_f64(f64) void;
	92	extern fn c_long_double(c_longdouble) void;
92	93
93	94	// On windows x64, the first 4 are passed via registers, others on the stack.
94	95	extern fn c_five_floats(f32, f32, f32, f32, f32) void;
...	...	@@ -105,6 +106,7 @@ test "C ABI floats" {
105	106	c_f32(12.34);
106	107	c_f64(56.78);
107	108	c_five_floats(1.0, 2.0, 3.0, 4.0, 5.0);
	109	c_long_double(12.34);
108	110	}
109	111
110	112	export fn zig_f32(x: f32) void {
...	...	@@ -113,6 +115,9 @@ export fn zig_f32(x: f32) void {
113	115	export fn zig_f64(x: f64) void {
114	116	expect(x == 56.78) catch @panic("test failure: zig_f64");
115	117	}
	118	export fn zig_longdouble(x: c_longdouble) void {
	119	expect(x == 12.34) catch @panic("test failure: zig_longdouble");
	120	}
116	121
117	122	extern fn c_ptr(*anyopaque) void;
118	123