Commit a7563e453dce0cc256a0c40af434731f2cf7dcaf | zig

author	Robin Voetter <robin@voetter.nl> 2023-04-08 19:02:31+02:00
committer	Robin Voetter <robin@voetter.nl> 2023-04-09 01:51:55+02:00
log	a7563e453dce0cc256a0c40af434731f2cf7dcaf
tree	a0483d968b31c6d5a90bb32312bf13af62c0b79d
parent	45b5f467709e3df01aafc37c25070bbbebd43e1e
signature	Commit is signed but in an unrecognized format.

spirv: minimal start code

For SPIR-V, only export the main function if it is actually declared. Kernel
entry points will often have parameters and more than one kernel declared.

In general, SPIR-V binaries should mostly be compiled as libraries and not as
executables. However, this start code is required so that we can build test
executables.

Note that a call to isSpirV() would emit the code for that function, even though
the call is at comptime. To save that function from being emitted the checks
are just inlined manually.

1 files changed, 10 insertions(+), 1 deletions(-)

lib
- std
  - start.zig

lib/std/start.zig+10-1

...	...	@@ -24,7 +24,9 @@ pub const simplified_logic =
24	24	builtin.zig_backend == .stage2_aarch64 or
25	25	builtin.zig_backend == .stage2_arm or
26	26	builtin.zig_backend == .stage2_riscv64 or
27		builtin.zig_backend == .stage2_sparc64;
	27	builtin.zig_backend == .stage2_sparc64 or
	28	builtin.cpu.arch == .spirv32 or
	29	builtin.cpu.arch == .spirv64;
28	30
29	31	comptime {
30	32	// No matter what, we import the root file, so that any export, test, comptime
...	...	@@ -43,6 +45,9 @@ comptime {
43	45	}
44	46	} else if (builtin.os.tag == .wasi and @hasDecl(root, "main")) {
45	47	@export(wasiMain2, .{ .name = "_start" });
	48	} else if (builtin.os.tag == .opencl) {
	49	if (@hasDecl(root, "main"))
	50	@export(spirvMain2, .{ .name = "main" });
46	51	} else {
47	52	if (!@hasDecl(root, "_start")) {
48	53	@export(_start2, .{ .name = "_start" });
...	...	@@ -127,6 +132,10 @@ fn wasiMain2() callconv(.C) noreturn {
127	132	}
128	133	}
129	134
	135	fn spirvMain2() callconv(.Kernel) void {
	136	root.main();
	137	}
	138
130	139	fn wWinMainCRTStartup2() callconv(.C) noreturn {
131	140	root.main();
132	141	exit2(0);