This fixes edge-cases, like the condition expression being a type-cast,
which DXC apparently sees as a variable re-declaration. Example:
fn foo(x : f32) {
switch (i32(x)) {
default {
}
}
}
was emitted as HLSL:
void foo(float x) {
int(x);
do {
} while (false);
}
The `int(x)` is seen as a re-declaration of `x` by DXC.
We fix this by only emitted the condition expression if it has
side-effects (which currently means it contains a call expression).
Bug: tint:1820
Change-Id: I7e4320fa09ea2d634c9e324cb0b752b0ee7dcde9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/118161
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: James Price <jrprice@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
eab1f62629