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/shader_io/interpolate_input_struct.wgsl.expected.msl b/test/shader_io/interpolate_input_struct.wgsl.expected.msl
index 285f608..edc350f 100644
--- a/test/shader_io/interpolate_input_struct.wgsl.expected.msl
+++ b/test/shader_io/interpolate_input_struct.wgsl.expected.msl
@@ -22,8 +22,12 @@
float linear_sample [[user(locn7)]] [[sample_no_perspective]];
};
+void tint_symbol_inner(In in) {
+}
+
fragment void tint_symbol(tint_symbol_2 tint_symbol_1 [[stage_in]]) {
- In const in = {.none=tint_symbol_1.none, .flat=tint_symbol_1.flat, .perspective_center=tint_symbol_1.perspective_center, .perspective_centroid=tint_symbol_1.perspective_centroid, .perspective_sample=tint_symbol_1.perspective_sample, .linear_center=tint_symbol_1.linear_center, .linear_centroid=tint_symbol_1.linear_centroid, .linear_sample=tint_symbol_1.linear_sample};
+ In const tint_symbol_3 = {.none=tint_symbol_1.none, .flat=tint_symbol_1.flat, .perspective_center=tint_symbol_1.perspective_center, .perspective_centroid=tint_symbol_1.perspective_centroid, .perspective_sample=tint_symbol_1.perspective_sample, .linear_center=tint_symbol_1.linear_center, .linear_centroid=tint_symbol_1.linear_centroid, .linear_sample=tint_symbol_1.linear_sample};
+ tint_symbol_inner(tint_symbol_3);
return;
}
