[glslang] Add impl for several matrix and constant op.

[ShchchowAMD]

Add impl for some ops, mainly for matrix and float / conv ops.

Finished op List:
(all of them have already been added to symbol table and related to a built-in op/function before, but not actually be implemented yet.)

EOpMatrixInverse
EOpTranspose
EOpPackSnorm2x16
EOpPackUnorm2x16
EOpPackHalf2x16
EOpUnpackSnorm2x16
EOpUnpackUnorm2x16
EOpUnpackHalf2x16
EOpDeterminant
EOpSinh
EOpCosh
EOpTanh
EOpAsinh
EOpAcosh
EOpAtanh
EOpFloatBitsToInt
EOpFloatBitsToUint
EOpIntBitsToFloat
EOpUintBitsToFloat
EOpDoubleBitsToInt64
EOpDoubleBitsToUint64
EOpInt64BitsToDouble
EOpUint64BitsToDouble
EOpMul (matrixCompMult)
EOpComma

[greg-lunarg]

This is a little ugly. The MachineIndependent module should be independent of any target module such as SPIRV.

There really is nothing about hex_float.h (and bitutils.h) that is related to SPIRV. They were brought in to support SPIRV and that is why they were placed there. They do have a spvutils namespace, but that is it.

How much work would it be to move these files into MachineIndependent and remove any reference of SPIRV from them?

[ShchchowAMD]

Yes, you are right.

The reason to include hex_float here is to keep those float/bit ops following same rules/implementation.

I'd have a try to refine the folder structure and namespace locally first.

[arcady-lunarg]

@ShchchowAMD do you intend to get back to this at some point?

[ShchchowAMD]

Thanks for reminding. I'll make a commit recently to fix issue discussed above.