[Compiler] In-progress support for vector float (AVX)

[water111]

Add basic support for vector floats.

• Add support in IGen for register->register moves
• Add support in IGen for usual GOAL loads and stores
• Add support in IGen for vmulps. This is a common format of instruction.
• Add support in IGen for vshufps.
• Add support in IGen for RIP-relative loads and stores
• Ability to load constant values (from a constant pool?)
• Clean up the two different RegKinds. Maybe a RegClass and a RegKind?
• Add support in rlet for creating a vf register
• Add support for load and store assembly operations in the front-end and IR
• Add support for basic 3-op assembly operations in the front-end and IR
• Add support for blend operations in the front-end
• Make sure coloring system is aware of vf registers. (Doesn't have to color them, just not clobber them)
• Implement a few functions in vector or vector-h as an example (may have to add more operations).
• Documentation for new asm forms.

[coveralls]

Pull Request Test Coverage Report for Build 453320586

• 778 of 871 (89.32%) changed or added relevant lines in 19 files are covered.
• 4 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.3%) to 81.141%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
common/type_system/TypeSystem.cpp	6	7	85.71%
goalc/compiler/Env.cpp	8	9	88.89%
goalc/regalloc/Allocator.cpp	7	10	70.0%
goalc/regalloc/IRegister.cpp	7	11	63.64%
goalc/compiler/IR.cpp	108	114	94.74%
goalc/compiler/Util.cpp	0	6	0.0%
goalc/emitter/Register.cpp	6	12	50.0%
common/type_system/Type.cpp	5	13	38.46%
goalc/emitter/IGen.h	139	147	94.56%
goalc/emitter/Instruction.h	204	228	89.47%

Files with Coverage Reduction	New Missed Lines	%
game/overlord/iso.cpp	1	77.86%
goalc/emitter/Register.cpp	3	82.61%

Totals
Change from base Build 449727383:	0.3%
Covered Lines:	18914
Relevant Lines:	23310

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💛 - Coveralls

[water111]

Getting close. The generated code for loading a constant vector is really bad:

(rlet ((vf1 :class vf :reset-here #t))
      (.lvf vf1 (new 'static 'vector :x 1.0 :y 1.2 :z 1.4 :w 1.6))
      )

becomes

- [0x10000] lea rax, [0x0000000000010007]          mov-sva igpr-1, static-structure
  [0x10007] sub rax, r15
  [0x1000a] vmovaps xmm0, [r15+rax*1]              mov ivf-0, [igpr-1 + 0]

it seems like we should support directly loading a static with .lvf.

[water111]

Now it is a single instruction (not linked, so the offset is wrong):

[0x10000] vmovaps xmm0, [0x0000000000010008]     mov-svl ivf-0, [static-structure]