Specification language to describe flat conversions and aggregate splats. #358
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@microsoft-github-policy-service agree company="Microsoft" |
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| \Sec{Array and Class splat conversion}{Conv.asplat} | ||
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| \p A glvalue of type \texttt{T} can be converted to a cxvalue of type |
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I believe that this conversion can only produce a prvalue, not a cxvalue. The only place cxvalues are created is for inout parameters, and I believe this code is invalid:
struct S {
float V[4];
};
void fn(inout float4 F) {}
export void call() {
S V = {1.xxxx};
fn((float4)V);
fn(V);
}| the value in the source vector replicated into each element of the flattened | ||
| \texttt{S}. | ||
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| \p A glvalue of type \texttt{T} can be converted to a cxvalue of type |
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There is an odd case for vector<->array conversions where we can create a cxvalue, but only from an explicit cast:
void fn(inout float4 F) {}
export void call() {
float V[4] = {1.xxxx};
fn((float4)V); // valid
fn(V); // invalid
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| of boolean type. A zero value is converted to \texttt{false}; all other values | |||
| are converted to \texttt{true}. | |||
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| \Sec{Flat conversion}{Conv.flat} | |||
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| \p There is a flattened order of subobjects for an aggregate, \texttt{A}, | |||
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I think this language is fine for now, but we should probably have some common definitions and unify this with the language in Decl.Init.Agg.
I filed #372 to track that separately.
| prvalue of type \texttt{U[]}, if there are valid conversions from | ||
| \texttt{T} to each \texttt{V} in flattened \texttt{U}. The destination value | ||
| is the source value \texttt{T} replicated into each element of the flattened | ||
| \texttt{U[]}. |
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U[] is not the same type as U[N], so we should be clear we're talking about sized arrays here.
Specification language to describe flat conversions and aggregate splats.