transform/shader_io: Generate a wrapper function
This is a major reworking of this transform. The old transform code
was getting unwieldy, with part of the complication coming from the
handling of multiple return statements. By generating a wrapper
function instead, we can avoid a lot of this complexity.
The original entry point function is stripped of all shader IO
attributes (as well as `stage` and `workgroup_size`), but the body is
left unmodified. A new entry point wrapper function is introduced
which calls the original function, packing/unpacking the shader inputs
as necessary, and propagates the result to the corresponding shader
outputs.
The new code has been refactored to use a state object with the
different parts of the transform split into separate functions, which
makes it much more manageable.
Fixed: tint:1076
Bug: tint:920
Change-Id: I3490a0ea7a3509a4e198ce730e476516649d8d96
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/60521
Auto-Submit: James Price <jrprice@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: James Price <jrprice@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
diff --git a/test/intrinsics/gen/all/bd2dba.wgsl.expected.hlsl b/test/intrinsics/gen/all/bd2dba.wgsl.expected.hlsl
index ca205bd..0650c24 100644
--- a/test/intrinsics/gen/all/bd2dba.wgsl.expected.hlsl
+++ b/test/intrinsics/gen/all/bd2dba.wgsl.expected.hlsl
@@ -6,10 +6,16 @@
float4 value : SV_Position;
};
-tint_symbol vertex_main() {
+float4 vertex_main_inner() {
all_bd2dba();
- const tint_symbol tint_symbol_1 = {float4(0.0f, 0.0f, 0.0f, 0.0f)};
- return tint_symbol_1;
+ return float4(0.0f, 0.0f, 0.0f, 0.0f);
+}
+
+tint_symbol vertex_main() {
+ const float4 inner_result = vertex_main_inner();
+ tint_symbol wrapper_result = (tint_symbol)0;
+ wrapper_result.value = inner_result;
+ return wrapper_result;
}
void fragment_main() {
