Correct preprocessor dependent expansion (#1270)

The DxilSigPoint.inl file depends on an esoteric distinction in how
different preprocessors expand macros included as parameters to
other macros.

When a macro receives another macro as its argument, different
preprocessors expand these parameter macros differently. MSVC
defers expanding the macro until the macros taking parameters
have been completely expanded. GCC and others expand the parameter
macro just as soon as it can.

At issue is the expansion of the three _## macros: _41, _50, and
_61 which expand to ,#,# respectively. These macros can be passed
into an initial macro that plugs them directly into a function that
takes multiple parameters without issue with any preprocessor.
Regardless of when the _## macro is expanded, it will be interpretted
correctly as passing multiple arguments to the function.

If the _## macro is passed into a parameterized macro that passes
it to another such parameterized macro that takes a single argument,
preprocessor inconsistencies come into play. If the preprocessor
expands the _## macro immediately, instead of passing the parameter
macro directly into the second paramaterized macro, the expansion
of the parameter macro will be passed in, which will be
interpretted as passing multiple arguments to a single-parameter
macro and an error will reseult. If the _## macro is not expanded
until the end, then it is expanded only for the final multi-
parameter function call as the author expected.

The simplest example of this is something like this:

define AB 1,2
define SEC(args) (args)
define FIRST(args) SEC(args)
  FIRST(_AB);

A preprocessor that delays expansion of _AB will expand thus:

FIRST(_AB) => SEC(_AB) => (_AB) => (1,2)

whereas an early expanding preprocessor will expand thus:

FIRST(_AB) => SEC(_AB) => SEC(1,2) => ERROR! SEC only takes 1 arg!

Some of the details of the example might be slightly off, but the
important thing is that the parameter gets expanded at different
times.

The solution to this is to complicate this already long macro.
The middle macro that introduces the opportunity for the _##
macros to be expanded early is DO_ROW, which doesn't do much
except allow for the larger data entry macro, DO_INTERPRETATION_TABLE
to be a bit shorter and simpler. By eliminating DO_ROW and
shortening the DO macro to D, the large table specifying behaviors
is only a little wider and harder to read and it no longer depends
on this inconsistent element of preprocessor behavior.

(I really hope that made sense. I wish I could come up with a
simpler explanation or solution. If any have suggestions for
either, I would be happy to adopt either. Feel free to email me.)

No functional change. Inching further toward cross-platform.

include/dxc/HLSL/DxilSigPoint.inl

@@ -49,37 +49,37 @@ const SigPoint SigPoint::ms_SigPoints[kNumSigPointRecords] = {
 
 // <py::lines('INTERPRETATION-TABLE')>hctdb_instrhelp.get_interpretation_table()</py>
 // INTERPRETATION-TABLE:BEGIN
-//   Semantic,               VSIn,         VSOut, PCIn,         HSIn,         HSCPIn, HSCPOut, PCOut,      DSIn,         DSCPIn, DSOut, GSVIn, GSIn,         GSOut, PSIn,          PSOut,         CSIn
-#define DO_INTERPRETATION_TABLE(DO) \
-  DO(Arbitrary,              Arb,          Arb,   NA,           NA,           Arb,    Arb,     Arb,        Arb,          Arb,    Arb,   Arb,   NA,           Arb,   Arb,           NA,            NA) \
-  DO(VertexID,               SV,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NA,            NA) \
-  DO(InstanceID,             SV,           Arb,   NA,           NA,           Arb,    Arb,     NA,         NA,           Arb,    Arb,   Arb,   NA,           Arb,   Arb,           NA,            NA) \
-  DO(Position,               Arb,          SV,    NA,           NA,           SV,     SV,      Arb,        Arb,          SV,     SV,    SV,    NA,           SV,    SV,            NA,            NA) \
-  DO(RenderTargetArrayIndex, Arb,          SV,    NA,           NA,           SV,     SV,      Arb,        Arb,          SV,     SV,    SV,    NA,           SV,    SV,            NA,            NA) \
-  DO(ViewPortArrayIndex,     Arb,          SV,    NA,           NA,           SV,     SV,      Arb,        Arb,          SV,     SV,    SV,    NA,           SV,    SV,            NA,            NA) \
-  DO(ClipDistance,           Arb,          SV,    NA,           NA,           SV,     SV,      Arb,        Arb,          SV,     SV,    SV,    NA,           SV,    SV,            NA,            NA) \
-  DO(CullDistance,           Arb,          SV,    NA,           NA,           SV,     SV,      Arb,        Arb,          SV,     SV,    SV,    NA,           SV,    SV,            NA,            NA) \
-  DO(OutputControlPointID,   NA,           NA,    NA,           NotInSig,     NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NA,            NA) \
-  DO(DomainLocation,         NA,           NA,    NA,           NA,           NA,     NA,      NA,         NotInSig,     NA,     NA,    NA,    NA,           NA,    NA,            NA,            NA) \
-  DO(PrimitiveID,            NA,           NA,    NotInSig,     NotInSig,     NA,     NA,      NA,         NotInSig,     NA,     NA,    NA,    Shadow,       SGV,   SGV,           NA,            NA) \
-  DO(GSInstanceID,           NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NotInSig,     NA,    NA,            NA,            NA) \
-  DO(SampleIndex,            NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    Shadow _41,    NA,            NA) \
-  DO(IsFrontFace,            NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           SGV,   SGV,           NA,            NA) \
-  DO(Coverage,               NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NotInSig _50,  NotPacked _41, NA) \
-  DO(InnerCoverage,          NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NotInSig _50,  NA,            NA) \
-  DO(Target,                 NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            Target,        NA) \
-  DO(Depth,                  NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NotPacked,     NA) \
-  DO(DepthLessEqual,         NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NotPacked _50, NA) \
-  DO(DepthGreaterEqual,      NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NotPacked _50, NA) \
-  DO(StencilRef,             NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NotPacked _50, NA) \
-  DO(DispatchThreadID,       NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NA,            NotInSig) \
-  DO(GroupID,                NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NA,            NotInSig) \
-  DO(GroupIndex,             NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NA,            NotInSig) \
-  DO(GroupThreadID,          NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NA,            NA,            NotInSig) \
-  DO(TessFactor,             NA,           NA,    NA,           NA,           NA,     NA,      TessFactor, TessFactor,   NA,     NA,    NA,    NA,           NA,    NA,            NA,            NA) \
-  DO(InsideTessFactor,       NA,           NA,    NA,           NA,           NA,     NA,      TessFactor, TessFactor,   NA,     NA,    NA,    NA,           NA,    NA,            NA,            NA) \
-  DO(ViewID,                 NotInSig _61, NA,    NotInSig _61, NotInSig _61, NA,     NA,      NA,         NotInSig _61, NA,     NA,    NA,    NotInSig _61, NA,    NotInSig _61,  NA,            NA) \
-  DO(Barycentrics,           NA,           NA,    NA,           NA,           NA,     NA,      NA,         NA,           NA,     NA,    NA,    NA,           NA,    NotPacked _61, NA,            NA)
+//  Semantic            VSIn,           VSOut,  PCIn,            HSIn,            HSCPIn, HSCPOut, PCOut,         DSIn,            DSCPIn, DSOut,  GSVIn,  GSIn,            GSOut,  PSIn,             PSOut,            CSIn
+#define DO_INTERPRETATION_TABLE(D) \
+  {/*Arbitrary*/        D(Arb),         D(Arb), D(NA),           D(NA),           D(Arb), D(Arb),  D(Arb),        D(Arb),          D(Arb), D(Arb), D(Arb), D(NA),           D(Arb), D(Arb),           D(NA),            D(NA)}, \
+  {/*VertexID*/         D(SV),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NA),            D(NA)}, \
+  {/*InstanceID*/       D(SV),          D(Arb), D(NA),           D(NA),           D(Arb), D(Arb),  D(NA),         D(NA),           D(Arb), D(Arb), D(Arb), D(NA),           D(Arb), D(Arb),           D(NA),            D(NA)}, \
+  {/*Position*/         D(Arb),         D(SV),  D(NA),           D(NA),           D(SV),  D(SV),   D(Arb),        D(Arb),          D(SV),  D(SV),  D(SV),  D(NA),           D(SV),  D(SV),            D(NA),            D(NA)}, \
+  {/*RenderTgArrayIdx*/ D(Arb),         D(SV),  D(NA),           D(NA),           D(SV),  D(SV),   D(Arb),        D(Arb),          D(SV),  D(SV),  D(SV),  D(NA),           D(SV),  D(SV),            D(NA),            D(NA)}, \
+  {/*ViewPortArrayIdx*/ D(Arb),         D(SV),  D(NA),           D(NA),           D(SV),  D(SV),   D(Arb),        D(Arb),          D(SV),  D(SV),  D(SV),  D(NA),           D(SV),  D(SV),            D(NA),            D(NA)}, \
+  {/*ClipDistance*/     D(Arb),         D(SV),  D(NA),           D(NA),           D(SV),  D(SV),   D(Arb),        D(Arb),          D(SV),  D(SV),  D(SV),  D(NA),           D(SV),  D(SV),            D(NA),            D(NA)}, \
+  {/*CullDistance*/     D(Arb),         D(SV),  D(NA),           D(NA),           D(SV),  D(SV),   D(Arb),        D(Arb),          D(SV),  D(SV),  D(SV),  D(NA),           D(SV),  D(SV),            D(NA),            D(NA)}, \
+  {/*OutputControlPtID*/D(NA),          D(NA),  D(NA),           D(NotInSig),     D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NA),            D(NA)}, \
+  {/*DomainLocation*/   D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NotInSig),     D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NA),            D(NA)}, \
+  {/*PrimitiveID*/      D(NA),          D(NA),  D(NotInSig),     D(NotInSig),     D(NA),  D(NA),   D(NA),         D(NotInSig),     D(NA),  D(NA),  D(NA),  D(Shadow),       D(SGV), D(SGV),           D(NA),            D(NA)}, \
+  {/*GSInstanceID*/     D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NotInSig),     D(NA),  D(NA),            D(NA),            D(NA)}, \
+  {/*SampleIndex*/      D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(Shadow _41),    D(NA),            D(NA)}, \
+  {/*IsFrontFace*/      D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(SGV), D(SGV),           D(NA),            D(NA)}, \
+  {/*Coverage*/         D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NotInSig _50),  D(NotPacked _41), D(NA)}, \
+  {/*InnerCoverage*/    D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NotInSig _50),  D(NA),            D(NA)}, \
+  {/*Target*/           D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(Target),        D(NA)}, \
+  {/*Depth*/            D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NotPacked),     D(NA)}, \
+  {/*DepthLessEqual*/   D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NotPacked _50), D(NA)}, \
+  {/*DepthGreaterEqual*/D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NotPacked _50), D(NA)}, \
+  {/*StencilRef*/       D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NotPacked _50), D(NA)}, \
+  {/*DispatchThreadID*/ D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NA),            D(NotInSig)}, \
+  {/*GroupID*/          D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NA),            D(NotInSig)}, \
+  {/*GroupIndex*/       D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NA),            D(NotInSig)}, \
+  {/*GroupThreadID*/    D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NA),            D(NotInSig)}, \
+  {/*TessFactor*/       D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(TessFactor), D(TessFactor),   D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NA),            D(NA)}, \
+  {/*InsideTessFactor*/ D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(TessFactor), D(TessFactor),   D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NA),            D(NA),            D(NA)}, \
+  {/*ViewID*/           D(NotInSig _61),D(NA),  D(NotInSig _61), D(NotInSig _61), D(NA),  D(NA),   D(NA),         D(NotInSig _61), D(NA),  D(NA),  D(NA),  D(NotInSig _61), D(NA),  D(NotInSig _61),  D(NA),            D(NA)}, \
+  {/*Barycentrics*/     D(NA),          D(NA),  D(NA),           D(NA),           D(NA),  D(NA),   D(NA),         D(NA),           D(NA),  D(NA),  D(NA),  D(NA),           D(NA),  D(NotPacked _61), D(NA),            D(NA)}, \
 // INTERPRETATION-TABLE:END
 
 const VersionedSemanticInterpretation SigPoint::ms_SemanticInterpretationTable[(unsigned)DXIL::SemanticKind::Invalid][(unsigned)SigPoint::Kind::Invalid] = {
@@ -87,10 +87,7 @@ const VersionedSemanticInterpretation SigPoint::ms_SemanticInterpretationTable[(
 #define _50 ,5,0
 #define _61 ,6,1
 #define DO(k) VersionedSemanticInterpretation(DXIL::SemanticInterpretationKind::k)
-#define DO_ROW(SEM, VSIn, VSOut, PCIn, HSIn, HSCPIn, HSCPOut, PCOut, DSIn, DSCPIn, DSOut, GSVIn, GSIn, GSOut, PSIn, PSOut, CSIn) \
-  { DO(VSIn), DO(VSOut), DO(PCIn), DO(HSIn), DO(HSCPIn), DO(HSCPOut), DO(PCOut), DO(DSIn), DO(DSCPIn), DO(DSOut), DO(GSVIn), DO(GSIn), DO(GSOut), DO(PSIn), DO(PSOut), DO(CSIn) },
-  DO_INTERPRETATION_TABLE(DO_ROW)
-#undef DO_ROW
+  DO_INTERPRETATION_TABLE(DO)
 #undef DO
 };