Commit a7563e453d

Robin Voetter <robin@voetter.nl>
2023-04-08 19:02:31
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.
master
1 parent 45b5f46
Changed files (1)
lib
std
start.zig
lib/std/start.zig
@@ -24,7 +24,9 @@ pub const simplified_logic =
     builtin.zig_backend == .stage2_aarch64 or
     builtin.zig_backend == .stage2_arm or
     builtin.zig_backend == .stage2_riscv64 or
-    builtin.zig_backend == .stage2_sparc64;
+    builtin.zig_backend == .stage2_sparc64 or
+    builtin.cpu.arch == .spirv32 or
+    builtin.cpu.arch == .spirv64;
 
 comptime {
     // No matter what, we import the root file, so that any export, test, comptime
@@ -43,6 +45,9 @@ comptime {
                 }
             } else if (builtin.os.tag == .wasi and @hasDecl(root, "main")) {
                 @export(wasiMain2, .{ .name = "_start" });
+            } else if (builtin.os.tag == .opencl) {
+                if (@hasDecl(root, "main"))
+                    @export(spirvMain2, .{ .name = "main" });
             } else {
                 if (!@hasDecl(root, "_start")) {
                     @export(_start2, .{ .name = "_start" });
@@ -127,6 +132,10 @@ fn wasiMain2() callconv(.C) noreturn {
     }
 }
 
+fn spirvMain2() callconv(.Kernel) void {
+    root.main();
+}
+
 fn wWinMainCRTStartup2() callconv(.C) noreturn {
     root.main();
     exit2(0);