Optimize vertex_shader_uid_data down to 28 bytes

This started as a fixing a misalignment issue, but I got carried away.
Was originally 41 bytes (overflowing it's expected 40 bytes by 1 bit).

Now it's 27 bytes plus 8 bits of padding (ready for future expansion).

The savings come from:
 - Removing UV usage from components, it can be reconstructed from
   texcoord_elem_count (saved 8 bits)
 - Removed the 8 unused bits from texMtxInfo_n_projection (saved 8 bits)
 - Removing unused bit from from start of components (saved 1 bit)
 - Removed extra bit from inputform, texgentype and sourcerow
 - packed texMtxInfo_n_projection and texcoord_elem_count back into
   the per texgen info space freed up above. (saved 24 bits)
 - Overlayed postMtx index and Emboss mode shifts into a union based on
   texgentype (saved 56 bits)
 - Move to a single-bit union tag, freeing up an extra bit for regular
   texgens.
 - Move PotMtx normalize into the freed up space (saved 8 bits)

Total savings: 105 bits of data

EDIT: Even worse, MSVC wasn't respecting pack(1) for bitfields at all,
      so on windows this struct was actually quite a bit larger.
      Something like 80 bytes, if not more.

      Fixed this by dropping the size of any enums used in these
      bit structs to u8. Our Common::BitField allows for the underlying
      type to be explicitly specified to something larger.

      msvc's bitfield packing appears to be completely braindead, can't
      mix sizes at all.

1 files changed, 8 insertions, 8 deletions

diff --git a/Source/Core/VideoCommon/XFMemory.h b/Source/Core/VideoCommon/XFMemory.h
index 4077e50859..04d22dc9f3 100644
--- a/Source/Core/VideoCommon/XFMemory.h
+++ b/Source/Core/VideoCommon/XFMemory.h
@@ -18,7 +18,7 @@ constexpr size_t NUM_XF_COLOR_CHANNELS = 2;
 // Lighting
 
 // Projection
-enum class TexSize : u32
+enum class TexSize : u8
 {
   ST = 0,
   STQ = 1
@@ -30,7 +30,7 @@ struct fmt::formatter<TexSize> : EnumFormatter<TexSize::STQ>
 };
 
 // Input form
-enum class TexInputForm : u32
+enum class TexInputForm : u8
 {
   AB11 = 0,
   ABC1 = 1
@@ -63,7 +63,7 @@ struct fmt::formatter<NormalCount> : EnumFormatter<NormalCount::Invalid>
 };
 
 // Texture generation type
-enum class TexGenType : u32
+enum class TexGenType : u8
 {
   Regular = 0,
   EmbossMap = 1,  // Used when bump mapping
@@ -83,7 +83,7 @@ struct fmt::formatter<TexGenType> : EnumFormatter<TexGenType::Color1>
 };
 
 // Source row
-enum class SourceRow : u32
+enum class SourceRow : u8
 {
   Geom = 0,    // Input is abc
   Normal = 1,  // Input is abc
@@ -318,11 +318,11 @@ struct fmt::formatter<INVTXSPEC>
 union TexMtxInfo
 {
   BitField<0, 1, u32> unknown;
-  BitField<1, 1, TexSize> projection;
-  BitField<2, 1, TexInputForm> inputform;
+  BitField<1, 1, TexSize, u32> projection;
+  BitField<2, 1, TexInputForm, u32> inputform;
   BitField<3, 1, u32> unknown2;
-  BitField<4, 3, TexGenType> texgentype;
-  BitField<7, 5, SourceRow> sourcerow;
+  BitField<4, 3, TexGenType, u32> texgentype;
+  BitField<7, 5, SourceRow, u32> sourcerow;
   BitField<12, 3, u32> embosssourceshift;  // what generated texcoord to use
   BitField<15, 3, u32> embosslightshift;   // light index that is used
   u32 hex;