dolphin/Source/Core/VideoCommon/VertexLoaderARM64.cpp

// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.

#include "Core/PowerPC/JitArm64/Jit.h"
#include "VideoCommon/VertexLoaderARM64.h"

using namespace Arm64Gen;

ARM64Reg src_reg = X0;
ARM64Reg dst_reg = X1;
ARM64Reg count_reg = W2;
ARM64Reg skipped_reg = W17;
ARM64Reg scratch1_reg = W16;
ARM64Reg scratch2_reg = W15;
ARM64Reg scratch3_reg = W14;
ARM64Reg scratch4_reg = W13;
ARM64Reg saved_count = W12;

ARM64Reg stride_reg = X11;
ARM64Reg arraybase_reg = X10;
ARM64Reg scale_reg = X9;

static const float GC_ALIGNED16(scale_factors[]) =
{
	1.0 / (1ULL <<  0), 1.0 / (1ULL <<  1), 1.0 / (1ULL <<  2), 1.0 / (1ULL <<  3),
	1.0 / (1ULL <<  4), 1.0 / (1ULL <<  5), 1.0 / (1ULL <<  6), 1.0 / (1ULL <<  7),
	1.0 / (1ULL <<  8), 1.0 / (1ULL <<  9), 1.0 / (1ULL << 10), 1.0 / (1ULL << 11),
	1.0 / (1ULL << 12), 1.0 / (1ULL << 13), 1.0 / (1ULL << 14), 1.0 / (1ULL << 15),
	1.0 / (1ULL << 16), 1.0 / (1ULL << 17), 1.0 / (1ULL << 18), 1.0 / (1ULL << 19),
	1.0 / (1ULL << 20), 1.0 / (1ULL << 21), 1.0 / (1ULL << 22), 1.0 / (1ULL << 23),
	1.0 / (1ULL << 24), 1.0 / (1ULL << 25), 1.0 / (1ULL << 26), 1.0 / (1ULL << 27),
	1.0 / (1ULL << 28), 1.0 / (1ULL << 29), 1.0 / (1ULL << 30), 1.0 / (1ULL << 31),
};

VertexLoaderARM64::VertexLoaderARM64(const TVtxDesc& vtx_desc, const VAT& vtx_att)
	: VertexLoaderBase(vtx_desc, vtx_att), m_float_emit(this)
{
	if (!IsInitialized())
		return;

	AllocCodeSpace(4096);
	ClearCodeSpace();
	GenerateVertexLoader();
	WriteProtect();
}

void VertexLoaderARM64::GetVertexAddr(int array, u64 attribute, ARM64Reg reg)
{
	ADD(reg, src_reg, m_src_ofs);
	if (attribute & MASK_INDEXED)
	{
		if (attribute == INDEX8)
		{
			LDRB(INDEX_UNSIGNED, scratch1_reg, reg, 0);
			m_src_ofs += 1;
		}
		else
		{
			LDRH(INDEX_UNSIGNED, scratch1_reg, reg, 0);
			m_src_ofs += 2;
			REV16(scratch1_reg, scratch1_reg);
		}

		if (array == ARRAY_POSITION)
		{
			EOR(scratch2_reg, scratch1_reg, 0, attribute == INDEX8 ? 7 : 15); // 0xFF : 0xFFFF
			m_skip_vertex = CBZ(scratch2_reg);
		}

		LDR(INDEX_UNSIGNED, scratch2_reg, stride_reg, array * 4);
		MUL(scratch1_reg, scratch1_reg, scratch2_reg);

		LDR(INDEX_UNSIGNED, EncodeRegTo64(scratch2_reg), arraybase_reg, array * 8);
		ADD(EncodeRegTo64(reg), EncodeRegTo64(scratch1_reg), EncodeRegTo64(scratch2_reg));
	}
}

s32 VertexLoaderARM64::GetAddressImm(int array, u64 attribute, Arm64Gen::ARM64Reg reg, u32 align)
{
	if (attribute & MASK_INDEXED || (m_src_ofs & (align - 1)))
		GetVertexAddr(array, attribute, reg);
	else
		return m_src_ofs;
	return -1;
}

int VertexLoaderARM64::ReadVertex(u64 attribute, int format, int count_in, int count_out, bool dequantize, u8 scaling_exponent, AttributeFormat* native_format)
{
	ARM64Reg coords = count_in == 3 ? Q31 : D31;
	ARM64Reg scale = count_in == 3 ? Q30 : D30;

	int elem_size = 1 << (format / 2);
	int load_bytes = elem_size * count_in;
	elem_size <<= 3;

	if (count_in == 1)
		m_float_emit.LDR(elem_size, INDEX_UNSIGNED, coords, EncodeRegTo64(scratch1_reg), 0);
	else
		m_float_emit.LD1(elem_size, 1, coords, EncodeRegTo64(scratch1_reg));

	if (format != FORMAT_FLOAT)
	{
		// Extend and convert to float
		switch (format)
		{
		case FORMAT_UBYTE:
			m_float_emit.UXTL(8, EncodeRegToDouble(coords), EncodeRegToDouble(coords));
			m_float_emit.UXTL(16, EncodeRegToDouble(coords), EncodeRegToDouble(coords));
		break;
		case FORMAT_BYTE:
			m_float_emit.SXTL(8, EncodeRegToDouble(coords), EncodeRegToDouble(coords));
			m_float_emit.SXTL(16, EncodeRegToDouble(coords), EncodeRegToDouble(coords));
		break;
		case FORMAT_USHORT:
			m_float_emit.REV16(8, EncodeRegToDouble(coords), EncodeRegToDouble(coords));
			m_float_emit.UXTL(16, EncodeRegToDouble(coords), EncodeRegToDouble(coords));
		break;
		case FORMAT_SHORT:
			m_float_emit.REV16(8, EncodeRegToDouble(coords), EncodeRegToDouble(coords));
			m_float_emit.SXTL(16, EncodeRegToDouble(coords), EncodeRegToDouble(coords));
		break;
		}

		m_float_emit.SCVTF(32, coords, coords);

		if (dequantize && scaling_exponent)
		{
			m_float_emit.LDR(32, INDEX_UNSIGNED, scale, scale_reg, scaling_exponent * 4);
			m_float_emit.FMUL(32, coords, coords, scale, 0);
		}
	}
	else
	{
		m_float_emit.REV32(8, coords, coords);
	}

	const u32 write_size = count_out == 3 ? 128 : count_out * 32;
	const u32 mask = count_out == 3 ? 0xF : count_out == 2 ? 0x7 : 0x3;
	if (!(m_dst_ofs & mask))
	{
		m_float_emit.STR(write_size, INDEX_UNSIGNED, coords, dst_reg, m_dst_ofs);

	}
	else
	{
		ADD(EncodeRegTo64(scratch2_reg), dst_reg, m_dst_ofs);
		m_float_emit.ST1(32, 1, coords, EncodeRegTo64(scratch2_reg));
	}

	native_format->components = count_out;
	native_format->enable = true;
	native_format->offset = m_dst_ofs;
	native_format->type = VAR_FLOAT;
	native_format->integer = false;
	m_dst_ofs += sizeof(float) * count_out;

	if (attribute == DIRECT)
		m_src_ofs += load_bytes;

	return load_bytes;
}

void VertexLoaderARM64::ReadColor(u64 attribute, int format, s32 offset)
{
	int load_bytes = 0;
	switch (format)
	{
		case FORMAT_24B_888:
		case FORMAT_32B_888x:
		case FORMAT_32B_8888:
			if (offset == -1)
				LDR(INDEX_UNSIGNED, scratch2_reg, EncodeRegTo64(scratch1_reg), 0);
			else
				LDR(INDEX_UNSIGNED, scratch2_reg, src_reg, m_src_ofs);

			if (format != FORMAT_32B_8888)
				ORR(scratch2_reg, scratch2_reg, 8, 7); // 0xFF000000
			STR(INDEX_UNSIGNED, scratch2_reg, dst_reg, m_dst_ofs);
			load_bytes = 3 + (format != FORMAT_24B_888);
			break;

		case FORMAT_16B_565:
			//                   RRRRRGGG GGGBBBBB
			// AAAAAAAA BBBBBBBB GGGGGGGG RRRRRRRR
			if (offset == -1)
				LDRH(INDEX_UNSIGNED, scratch3_reg, EncodeRegTo64(scratch1_reg), 0);
			else
				LDRH(INDEX_UNSIGNED, scratch3_reg, src_reg, m_src_ofs);

			REV16(scratch3_reg, scratch3_reg);

			// B
			AND(scratch2_reg, scratch3_reg, 32, 4);
			ORR(scratch2_reg, WSP, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 3));
			ORR(scratch2_reg, scratch2_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSR, 5));
			ORR(scratch1_reg, WSP, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 16));

			// G
			UBFM(scratch2_reg, scratch3_reg, 5, 10);
			ORR(scratch2_reg, WSP, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 2));
			ORR(scratch2_reg, scratch2_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSR, 6));
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 8));

			// R
			UBFM(scratch2_reg, scratch3_reg, 11, 15);
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 3));
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSR, 2));

			// A
			ORR(scratch2_reg, scratch2_reg, 8, 7); // 0xFF000000

			STR(INDEX_UNSIGNED, scratch1_reg, dst_reg, m_dst_ofs);
			load_bytes = 2;
			break;

		case FORMAT_16B_4444:
			//                   BBBBAAAA RRRRGGGG
			//           REV16 - RRRRGGGG BBBBAAAA
			// AAAAAAAA BBBBBBBB GGGGGGGG RRRRRRRR
			if (offset == -1)
				LDRH(INDEX_UNSIGNED, scratch3_reg, EncodeRegTo64(scratch1_reg), 0);
			else
				LDRH(INDEX_UNSIGNED, scratch3_reg, src_reg, m_src_ofs);

			// R
			UBFM(scratch1_reg, scratch3_reg, 4, 7);

			// G
			AND(scratch2_reg, scratch3_reg, 32, 3);
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 8));

			// B
			UBFM(scratch2_reg, scratch3_reg, 12, 15);
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 16));

			// A
			UBFM(scratch2_reg, scratch3_reg, 8, 11);
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 24));

			// Final duplication
			ORR(scratch1_reg, scratch1_reg, scratch1_reg, ArithOption(scratch1_reg, ST_LSL, 4));

			STR(INDEX_UNSIGNED, scratch1_reg, dst_reg, m_dst_ofs);
			load_bytes = 2;
			break;

		case FORMAT_24B_6666:
			//          RRRRRRGG GGGGBBBB BBAAAAAA
			// AAAAAAAA BBBBBBBB GGGGGGGG RRRRRRRR
			if (offset == -1)
				LDR(INDEX_UNSIGNED, scratch3_reg, EncodeRegTo64(scratch1_reg), 0);
			else
				LDR(INDEX_UNSIGNED, scratch3_reg, src_reg, m_src_ofs);

			REV32(scratch3_reg, scratch3_reg);

			// A
			AND(scratch2_reg, scratch3_reg, 32, 5);
			ORR(scratch2_reg, WSP, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 2));
			ORR(scratch2_reg, scratch2_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSR, 6));
			ORR(scratch1_reg, WSP, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 24));

			// B
			UBFM(scratch2_reg, scratch3_reg, 6, 11);
			ORR(scratch2_reg, WSP, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 2));
			ORR(scratch2_reg, scratch2_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSR, 6));
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 16));

			// G
			UBFM(scratch2_reg, scratch3_reg, 12, 17);
			ORR(scratch2_reg, WSP, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 2));
			ORR(scratch2_reg, scratch2_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSR, 6));
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 8));

			// R
			UBFM(scratch2_reg, scratch3_reg, 18, 23);
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSL, 2));
			ORR(scratch1_reg, scratch1_reg, scratch2_reg, ArithOption(scratch2_reg, ST_LSR, 4));

			STR(INDEX_UNSIGNED, scratch1_reg, dst_reg, m_dst_ofs);
			load_bytes = 3;
			break;
	}
	if (attribute == DIRECT)
		m_src_ofs += load_bytes;
}

void VertexLoaderARM64::GenerateVertexLoader()
{
	// R0 - Source pointer
	// R1 - Destination pointer
	// R2 - Count
	// R30 - LR
	//
	// R0 return how many
	//
	// Registers we don't have to worry about saving
	// R9-R17 are caller saved temporaries
	// R18 is a temporary or platform specific register(iOS)
	//
	// VFP registers
	// We can touch all except v8-v15
	// If we need to use those, we need to retain the lower 64bits(!) of the register

	MOV(skipped_reg, WSP);
	MOV(saved_count, count_reg);

	MOVI2R(stride_reg, (u64)&g_main_cp_state.array_strides);
	MOVI2R(arraybase_reg, (u64)&cached_arraybases);
	MOVI2R(scale_reg, (u64)&scale_factors);

	const u8* loop_start = GetCodePtr();

	if (m_VtxDesc.PosMatIdx)
	{
		LDRB(INDEX_UNSIGNED, scratch1_reg, src_reg, m_src_ofs);
		AND(scratch1_reg, scratch1_reg, 0, 5);
		STR(INDEX_UNSIGNED, scratch1_reg, dst_reg, m_dst_ofs);
		m_native_components |= VB_HAS_POSMTXIDX;
		m_native_vtx_decl.posmtx.components = 4;
		m_native_vtx_decl.posmtx.enable = true;
		m_native_vtx_decl.posmtx.offset = m_dst_ofs;
		m_native_vtx_decl.posmtx.type = VAR_UNSIGNED_BYTE;
		m_native_vtx_decl.posmtx.integer = true;
		m_src_ofs += sizeof(u8);
		m_dst_ofs += sizeof(u32);
	}

	u32 texmatidx_ofs[8];
	const u64 tm[8] = {
		m_VtxDesc.Tex0MatIdx, m_VtxDesc.Tex1MatIdx, m_VtxDesc.Tex2MatIdx, m_VtxDesc.Tex3MatIdx,
		m_VtxDesc.Tex4MatIdx, m_VtxDesc.Tex5MatIdx, m_VtxDesc.Tex6MatIdx, m_VtxDesc.Tex7MatIdx,
	};
	for (int i = 0; i < 8; i++)
	{
		if (tm[i])
			texmatidx_ofs[i] = m_src_ofs++;
	}

	GetVertexAddr(ARRAY_POSITION, m_VtxDesc.Position, EncodeRegTo64(scratch1_reg));
	ReadVertex(m_VtxDesc.Position, m_VtxAttr.PosFormat, m_VtxAttr.PosElements + 2, 3,
	           m_VtxAttr.ByteDequant, m_VtxAttr.PosFrac, &m_native_vtx_decl.position);

	if (m_VtxDesc.Normal)
	{
		static const u8 map[8] = {7, 6, 15, 14};
		u8 scaling_exponent = map[m_VtxAttr.NormalFormat];

		for (int i = 0; i < (m_VtxAttr.NormalElements ? 3 : 1); i++)
		{
			if (!i || m_VtxAttr.NormalIndex3)
			{
				GetVertexAddr(ARRAY_NORMAL, m_VtxDesc.Normal, EncodeRegTo64(scratch1_reg));
				int elem_size = 1 << (m_VtxAttr.NormalFormat / 2);
				ADD(EncodeRegTo64(scratch1_reg), EncodeRegTo64(scratch1_reg), i * elem_size * 3);
			}
			int bytes_read = ReadVertex(m_VtxDesc.Normal, m_VtxAttr.NormalFormat, 3, 3,
			                            true, scaling_exponent, &m_native_vtx_decl.normals[i]);

			ADD(EncodeRegTo64(scratch1_reg), EncodeRegTo64(scratch1_reg), bytes_read);
		}

		m_native_components |= VB_HAS_NRM0;
		if (m_VtxAttr.NormalElements)
			m_native_components |= VB_HAS_NRM1 | VB_HAS_NRM2;
	}

	const u64 col[2] = {m_VtxDesc.Color0, m_VtxDesc.Color1};
	for (int i = 0; i < 2; i++)
	{
		m_native_vtx_decl.colors[i].components = 4;
		m_native_vtx_decl.colors[i].type = VAR_UNSIGNED_BYTE;
		m_native_vtx_decl.colors[i].integer = false;

		if (col[i])
		{
			u32 align = 4;
			if (m_VtxAttr.color[i].Comp == FORMAT_16B_565 ||
			    m_VtxAttr.color[i].Comp == FORMAT_16B_4444)
				align = 2;

			s32 offset = GetAddressImm(ARRAY_COLOR + i, col[i], EncodeRegTo64(scratch1_reg), align);
			ReadColor(col[i], m_VtxAttr.color[i].Comp, offset);
			m_native_components |= VB_HAS_COL0 << i;
			m_native_vtx_decl.colors[i].components = 4;
			m_native_vtx_decl.colors[i].enable = true;
			m_native_vtx_decl.colors[i].offset = m_dst_ofs;
			m_native_vtx_decl.colors[i].type = VAR_UNSIGNED_BYTE;
			m_native_vtx_decl.colors[i].integer = false;
			m_dst_ofs += 4;
		}
	}

	const u64 tc[8] = {
		m_VtxDesc.Tex0Coord, m_VtxDesc.Tex1Coord, m_VtxDesc.Tex2Coord, m_VtxDesc.Tex3Coord,
		m_VtxDesc.Tex4Coord, m_VtxDesc.Tex5Coord, m_VtxDesc.Tex6Coord, m_VtxDesc.Tex7Coord,
	};

	for (int i = 0; i < 8; i++)
	{
		m_native_vtx_decl.texcoords[i].offset = m_dst_ofs;
		m_native_vtx_decl.texcoords[i].type = VAR_FLOAT;
		m_native_vtx_decl.texcoords[i].integer = false;

		int elements = m_VtxAttr.texCoord[i].Elements + 1;
		if (tc[i])
		{
			m_native_components |= VB_HAS_UV0 << i;
			GetVertexAddr(ARRAY_TEXCOORD0 + i, tc[i], EncodeRegTo64(scratch1_reg));
			u8 scaling_exponent = m_VtxAttr.texCoord[i].Frac;
			ReadVertex(tc[i], m_VtxAttr.texCoord[i].Format, elements, tm[i] ? 2 : elements,
			           m_VtxAttr.ByteDequant, scaling_exponent, &m_native_vtx_decl.texcoords[i]);
		}
		if (tm[i])
		{
			m_native_components |= VB_HAS_TEXMTXIDX0 << i;
			m_native_vtx_decl.texcoords[i].components = 3;
			m_native_vtx_decl.texcoords[i].enable = true;
			m_native_vtx_decl.texcoords[i].type = VAR_FLOAT;
			m_native_vtx_decl.texcoords[i].integer = false;

			LDRB(INDEX_UNSIGNED, scratch2_reg, src_reg, texmatidx_ofs[i]);
			m_float_emit.UCVTF(S31, scratch2_reg);

			if (tc[i])
			{
				m_float_emit.STR(32, INDEX_UNSIGNED, D31, dst_reg, m_dst_ofs);
				m_dst_ofs += sizeof(float);
			}
			else
			{
				m_native_vtx_decl.texcoords[i].offset = m_dst_ofs;

				if (!(m_dst_ofs & 7))
				{
					// If m_dst_ofs isn't 8byte aligned we can't store an 8byte zero register
					// So store two 4byte zero registers
					// The destination is always 4byte aligned
					STR(INDEX_UNSIGNED, WSP, dst_reg, m_dst_ofs);
					STR(INDEX_UNSIGNED, WSP, dst_reg, m_dst_ofs + 4);
					m_float_emit.STR(32, INDEX_UNSIGNED, D31, dst_reg, m_dst_ofs + 8);
				}
				else
				{
					STR(INDEX_UNSIGNED, SP, dst_reg, m_dst_ofs);
					m_float_emit.STR(32, INDEX_UNSIGNED, D31, dst_reg, m_dst_ofs + 8);
				}
				m_dst_ofs += sizeof(float) * 3;
			}
		}
	}

	// Prepare for the next vertex.
	ADD(dst_reg, dst_reg, m_dst_ofs);
	const u8* cont = GetCodePtr();
	ADD(src_reg, src_reg, m_src_ofs);

	SUB(count_reg, count_reg, 1);
	CBNZ(count_reg, loop_start);

	if (m_VtxDesc.Position & MASK_INDEXED)
	{
		SUB(W0, saved_count, skipped_reg);
		RET(X30);

		SetJumpTarget(m_skip_vertex);
		ADD(skipped_reg, skipped_reg, 1);
		B(cont);
	}
	else
	{
		MOV(W0, saved_count);
		RET(X30);
	}

	FlushIcache();

	m_VertexSize = m_src_ofs;
	m_native_vtx_decl.stride = m_dst_ofs;
}

int VertexLoaderARM64::RunVertices(DataReader src, DataReader dst, int count, int primitive)
{
	m_numLoadedVertices += count;
	return ((int (*)(u8* src, u8* dst, int count))region)(src.GetPointer(), dst.GetPointer(), count);
}