src/Pipeline/SpirvShaderArithmetic.cpp - SwiftShader - Git at Google

 // Copyright 2019 The SwiftShader Authors. All Rights Reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //    http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 #include "SpirvShader.hpp"
 #include "SpirvShaderDebug.hpp"

 #include "ShaderCore.hpp"

 #include <spirv/unified1/spirv.hpp>

 namespace sw {

 SpirvShader::EmitResult SpirvShader::EmitVectorTimesScalar(InsnIterator insn, EmitState *state) const
 {
 	auto &type = getType(insn.resultTypeId());
 	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
 	auto lhs = Operand(this, state, insn.word(3));
 	auto rhs = Operand(this, state, insn.word(4));

 	for(auto i = 0u; i < type.componentCount; i++)
 	{
 		dst.move(i, lhs.Float(i) * rhs.Float(0));
 	}

 	return EmitResult::Continue;
 }

 SpirvShader::EmitResult SpirvShader::EmitMatrixTimesVector(InsnIterator insn, EmitState *state) const
 {
 	auto &type = getType(insn.resultTypeId());
 	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
 	auto lhs = Operand(this, state, insn.word(3));
 	auto rhs = Operand(this, state, insn.word(4));

 	for(auto i = 0u; i < type.componentCount; i++)
 	{
 		SIMD::Float v = lhs.Float(i) * rhs.Float(0);
 		for(auto j = 1u; j < rhs.componentCount; j++)
 		{
 			v += lhs.Float(i + type.componentCount * j) * rhs.Float(j);
 		}
 		dst.move(i, v);
 	}

 	return EmitResult::Continue;
 }

 SpirvShader::EmitResult SpirvShader::EmitVectorTimesMatrix(InsnIterator insn, EmitState *state) const
 {
 	auto &type = getType(insn.resultTypeId());
 	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
 	auto lhs = Operand(this, state, insn.word(3));
 	auto rhs = Operand(this, state, insn.word(4));

 	for(auto i = 0u; i < type.componentCount; i++)
 	{
 		SIMD::Float v = lhs.Float(0) * rhs.Float(i * lhs.componentCount);
 		for(auto j = 1u; j < lhs.componentCount; j++)
 		{
 			v += lhs.Float(j) * rhs.Float(i * lhs.componentCount + j);
 		}
 		dst.move(i, v);
 	}

 	return EmitResult::Continue;
 }

 SpirvShader::EmitResult SpirvShader::EmitMatrixTimesMatrix(InsnIterator insn, EmitState *state) const
 {
 	auto &type = getType(insn.resultTypeId());
 	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
 	auto lhs = Operand(this, state, insn.word(3));
 	auto rhs = Operand(this, state, insn.word(4));

 	auto numColumns = type.definition.word(3);
 	auto numRows = getType(type.definition.word(2)).definition.word(3);
 	auto numAdds = getObjectType(insn.word(3)).definition.word(3);

 	for(auto row = 0u; row < numRows; row++)
 	{
 		for(auto col = 0u; col < numColumns; col++)
 		{
 			SIMD::Float v = SIMD::Float(0);
 			for(auto i = 0u; i < numAdds; i++)
 			{
 				v += lhs.Float(i * numRows + row) * rhs.Float(col * numAdds + i);
 			}
 			dst.move(numRows * col + row, v);
 		}
 	}

 	return EmitResult::Continue;
 }

 SpirvShader::EmitResult SpirvShader::EmitOuterProduct(InsnIterator insn, EmitState *state) const
 {
 	auto &type = getType(insn.resultTypeId());
 	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
 	auto lhs = Operand(this, state, insn.word(3));
 	auto rhs = Operand(this, state, insn.word(4));

 	auto numRows = lhs.componentCount;
 	auto numCols = rhs.componentCount;

 	for(auto col = 0u; col < numCols; col++)
 	{
 		for(auto row = 0u; row < numRows; row++)
 		{
 			dst.move(col * numRows + row, lhs.Float(row) * rhs.Float(col));
 		}
 	}

 	return EmitResult::Continue;
 }

 SpirvShader::EmitResult SpirvShader::EmitTranspose(InsnIterator insn, EmitState *state) const
 {
 	auto &type = getType(insn.resultTypeId());
 	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
 	auto mat = Operand(this, state, insn.word(3));

 	auto numCols = type.definition.word(3);
 	auto numRows = getType(type.definition.word(2)).componentCount;

 	for(auto col = 0u; col < numCols; col++)
 	{
 		for(auto row = 0u; row < numRows; row++)
 		{
 			dst.move(col * numRows + row, mat.Float(row * numCols + col));
 		}
 	}

 	return EmitResult::Continue;
 }

 SpirvShader::EmitResult SpirvShader::EmitUnaryOp(InsnIterator insn, EmitState *state) const
 {
 	auto &type = getType(insn.resultTypeId());
 	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
 	auto src = Operand(this, state, insn.word(3));

 	for(auto i = 0u; i < type.componentCount; i++)
 	{
 		switch(insn.opcode())
 		{
 		case spv::OpNot:
 		case spv::OpLogicalNot:  // logical not == bitwise not due to all-bits boolean representation
 			dst.move(i, ~src.UInt(i));
 			break;
 		case spv::OpBitFieldInsert:
 			{
 				auto insert = Operand(this, state, insn.word(4)).UInt(i);
 				auto offset = Operand(this, state, insn.word(5)).UInt(0);
 				auto count = Operand(this, state, insn.word(6)).UInt(0);
 				auto one = SIMD::UInt(1);
 				auto v = src.UInt(i);
 				auto mask = Bitmask32(offset + count) ^ Bitmask32(offset);
 				dst.move(i, (v & ~mask) | ((insert << offset) & mask));
 			}
 			break;
 		case spv::OpBitFieldSExtract:
 		case spv::OpBitFieldUExtract:
 			{
 				auto offset = Operand(this, state, insn.word(4)).UInt(0);
 				auto count = Operand(this, state, insn.word(5)).UInt(0);
 				auto one = SIMD::UInt(1);
 				auto v = src.UInt(i);
 				SIMD::UInt out = (v >> offset) & Bitmask32(count);
 				if(insn.opcode() == spv::OpBitFieldSExtract)
 				{
 					auto sign = out & NthBit32(count - one);
 					auto sext = ~(sign - one);
 					out |= sext;
 				}
 				dst.move(i, out);
 			}
 			break;
 		case spv::OpBitReverse:
 			{
 				// TODO: Add an intrinsic to reactor. Even if there isn't a
 				// single vector instruction, there may be target-dependent
 				// ways to make this faster.
 				// https://graphics.stanford.edu/~seander/bithacks.html#ReverseParallel
 				SIMD::UInt v = src.UInt(i);
 				v = ((v >> 1) & SIMD::UInt(0x55555555)) | ((v & SIMD::UInt(0x55555555)) << 1);
 				v = ((v >> 2) & SIMD::UInt(0x33333333)) | ((v & SIMD::UInt(0x33333333)) << 2);
 				v = ((v >> 4) & SIMD::UInt(0x0F0F0F0F)) | ((v & SIMD::UInt(0x0F0F0F0F)) << 4);
 				v = ((v >> 8) & SIMD::UInt(0x00FF00FF)) | ((v & SIMD::UInt(0x00FF00FF)) << 8);
 				v = (v >> 16) | (v << 16);
 				dst.move(i, v);
 			}
 			break;
 		case spv::OpBitCount:
 			dst.move(i, CountBits(src.UInt(i)));
 			break;
 		case spv::OpSNegate:
 			dst.move(i, -src.Int(i));
 			break;
 		case spv::OpFNegate:
 			dst.move(i, -src.Float(i));
 			break;
 		case spv::OpConvertFToU:
 			dst.move(i, SIMD::UInt(src.Float(i)));
 			break;
 		case spv::OpConvertFToS:
 			dst.move(i, SIMD::Int(src.Float(i)));
 			break;
 		case spv::OpConvertSToF:
 			dst.move(i, SIMD::Float(src.Int(i)));
 			break;
 		case spv::OpConvertUToF:
 			dst.move(i, SIMD::Float(src.UInt(i)));
 			break;
 		case spv::OpBitcast:
 			dst.move(i, src.Float(i));
 			break;
 		case spv::OpIsInf:
 			dst.move(i, IsInf(src.Float(i)));
 			break;
 		case spv::OpIsNan:
 			dst.move(i, IsNan(src.Float(i)));
 			break;
 		case spv::OpDPdx:
 		case spv::OpDPdxCoarse:
 			// Derivative instructions: FS invocations are laid out like so:
 			//    0 1
 			//    2 3
 			static_assert(SIMD::Width == 4, "All cross-lane instructions will need care when using a different width");
 			dst.move(i, SIMD::Float(Extract(src.Float(i), 1) - Extract(src.Float(i), 0)));
 			break;
 		case spv::OpDPdy:
 		case spv::OpDPdyCoarse:
 			dst.move(i, SIMD::Float(Extract(src.Float(i), 2) - Extract(src.Float(i), 0)));
 			break;
 		case spv::OpFwidth:
 		case spv::OpFwidthCoarse:
 			dst.move(i, SIMD::Float(Abs(Extract(src.Float(i), 1) - Extract(src.Float(i), 0)) + Abs(Extract(src.Float(i), 2) - Extract(src.Float(i), 0))));
 			break;
 		case spv::OpDPdxFine:
 			{
 				auto firstRow = Extract(src.Float(i), 1) - Extract(src.Float(i), 0);
 				auto secondRow = Extract(src.Float(i), 3) - Extract(src.Float(i), 2);
 				SIMD::Float v = SIMD::Float(firstRow);
 				v = Insert(v, secondRow, 2);
 				v = Insert(v, secondRow, 3);
 				dst.move(i, v);
 			}
 			break;
 		case spv::OpDPdyFine:
 			{
 				auto firstColumn = Extract(src.Float(i), 2) - Extract(src.Float(i), 0);
 				auto secondColumn = Extract(src.Float(i), 3) - Extract(src.Float(i), 1);
 				SIMD::Float v = SIMD::Float(firstColumn);
 				v = Insert(v, secondColumn, 1);
 				v = Insert(v, secondColumn, 3);
 				dst.move(i, v);
 			}
 			break;
 		case spv::OpFwidthFine:
 			{
 				auto firstRow = Extract(src.Float(i), 1) - Extract(src.Float(i), 0);
 				auto secondRow = Extract(src.Float(i), 3) - Extract(src.Float(i), 2);
 				SIMD::Float dpdx = SIMD::Float(firstRow);
 				dpdx = Insert(dpdx, secondRow, 2);
 				dpdx = Insert(dpdx, secondRow, 3);
 				auto firstColumn = Extract(src.Float(i), 2) - Extract(src.Float(i), 0);
 				auto secondColumn = Extract(src.Float(i), 3) - Extract(src.Float(i), 1);
 				SIMD::Float dpdy = SIMD::Float(firstColumn);
 				dpdy = Insert(dpdy, secondColumn, 1);
 				dpdy = Insert(dpdy, secondColumn, 3);
 				dst.move(i, Abs(dpdx) + Abs(dpdy));
 			}
 			break;
 		case spv::OpQuantizeToF16:
 			{
 				// Note: keep in sync with the specialization constant version in EvalSpecConstantUnaryOp
 				auto abs = Abs(src.Float(i));
 				auto sign = src.Int(i) & SIMD::Int(0x80000000);
 				auto isZero = CmpLT(abs, SIMD::Float(0.000061035f));
 				auto isInf = CmpGT(abs, SIMD::Float(65504.0f));
 				auto isNaN = IsNan(abs);
 				auto isInfOrNan = isInf | isNaN;
 				SIMD::Int v = src.Int(i) & SIMD::Int(0xFFFFE000);
 				v &= ~isZero | SIMD::Int(0x80000000);
 				v = sign | (isInfOrNan & SIMD::Int(0x7F800000)) | (~isInfOrNan & v);
 				v |= isNaN & SIMD::Int(0x400000);
 				dst.move(i, v);
 			}
 			break;
 		default:
 			UNREACHABLE("%s", OpcodeName(insn.opcode()));
 		}
 	}

 	return EmitResult::Continue;
 }

 SpirvShader::EmitResult SpirvShader::EmitBinaryOp(InsnIterator insn, EmitState *state) const
 {
 	auto &type = getType(insn.resultTypeId());
 	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
 	auto &lhsType = getObjectType(insn.word(3));
 	auto lhs = Operand(this, state, insn.word(3));
 	auto rhs = Operand(this, state, insn.word(4));

 	for(auto i = 0u; i < lhsType.componentCount; i++)
 	{
 		switch(insn.opcode())
 		{
 		case spv::OpIAdd:
 			dst.move(i, lhs.Int(i) + rhs.Int(i));
 			break;
 		case spv::OpISub:
 			dst.move(i, lhs.Int(i) - rhs.Int(i));
 			break;
 		case spv::OpIMul:
 			dst.move(i, lhs.Int(i) * rhs.Int(i));
 			break;
 		case spv::OpSDiv:
 			{
 				SIMD::Int a = lhs.Int(i);
 				SIMD::Int b = rhs.Int(i);
 				b = b | CmpEQ(b, SIMD::Int(0));                                       // prevent divide-by-zero
 				a = a | (CmpEQ(a, SIMD::Int(0x80000000)) & CmpEQ(b, SIMD::Int(-1)));  // prevent integer overflow
 				dst.move(i, a / b);
 			}
 			break;
 		case spv::OpUDiv:
 			{
 				auto zeroMask = As<SIMD::UInt>(CmpEQ(rhs.Int(i), SIMD::Int(0)));
 				dst.move(i, lhs.UInt(i) / (rhs.UInt(i) | zeroMask));
 			}
 			break;
 		case spv::OpSRem:
 			{
 				SIMD::Int a = lhs.Int(i);
 				SIMD::Int b = rhs.Int(i);
 				b = b | CmpEQ(b, SIMD::Int(0));                                       // prevent divide-by-zero
 				a = a | (CmpEQ(a, SIMD::Int(0x80000000)) & CmpEQ(b, SIMD::Int(-1)));  // prevent integer overflow
 				dst.move(i, a % b);
 			}
 			break;
 		case spv::OpSMod:
 			{
 				SIMD::Int a = lhs.Int(i);
 				SIMD::Int b = rhs.Int(i);
 				b = b | CmpEQ(b, SIMD::Int(0));                                       // prevent divide-by-zero
 				a = a | (CmpEQ(a, SIMD::Int(0x80000000)) & CmpEQ(b, SIMD::Int(-1)));  // prevent integer overflow
 				auto mod = a % b;
 				// If a and b have opposite signs, the remainder operation takes
 				// the sign from a but OpSMod is supposed to take the sign of b.
 				// Adding b will ensure that the result has the correct sign and
 				// that it is still congruent to a modulo b.
 				//
 				// See also http://mathforum.org/library/drmath/view/52343.html
 				auto signDiff = CmpNEQ(CmpGE(a, SIMD::Int(0)), CmpGE(b, SIMD::Int(0)));
 				auto fixedMod = mod + (b & CmpNEQ(mod, SIMD::Int(0)) & signDiff);
 				dst.move(i, As<SIMD::Float>(fixedMod));
 			}
 			break;
 		case spv::OpUMod:
 			{
 				auto zeroMask = As<SIMD::UInt>(CmpEQ(rhs.Int(i), SIMD::Int(0)));
 				dst.move(i, lhs.UInt(i) % (rhs.UInt(i) | zeroMask));
 			}
 			break;
 		case spv::OpIEqual:
 		case spv::OpLogicalEqual:
 			dst.move(i, CmpEQ(lhs.Int(i), rhs.Int(i)));
 			break;
 		case spv::OpINotEqual:
 		case spv::OpLogicalNotEqual:
 			dst.move(i, CmpNEQ(lhs.Int(i), rhs.Int(i)));
 			break;
 		case spv::OpUGreaterThan:
 			dst.move(i, CmpGT(lhs.UInt(i), rhs.UInt(i)));
 			break;
 		case spv::OpSGreaterThan:
 			dst.move(i, CmpGT(lhs.Int(i), rhs.Int(i)));
 			break;
 		case spv::OpUGreaterThanEqual:
 			dst.move(i, CmpGE(lhs.UInt(i), rhs.UInt(i)));
 			break;
 		case spv::OpSGreaterThanEqual:
 			dst.move(i, CmpGE(lhs.Int(i), rhs.Int(i)));
 			break;
 		case spv::OpULessThan:
 			dst.move(i, CmpLT(lhs.UInt(i), rhs.UInt(i)));
 			break;
 		case spv::OpSLessThan:
 			dst.move(i, CmpLT(lhs.Int(i), rhs.Int(i)));
 			break;
 		case spv::OpULessThanEqual:
 			dst.move(i, CmpLE(lhs.UInt(i), rhs.UInt(i)));
 			break;
 		case spv::OpSLessThanEqual:
 			dst.move(i, CmpLE(lhs.Int(i), rhs.Int(i)));
 			break;
 		case spv::OpFAdd:
 			dst.move(i, lhs.Float(i) + rhs.Float(i));
 			break;
 		case spv::OpFSub:
 			dst.move(i, lhs.Float(i) - rhs.Float(i));
 			break;
 		case spv::OpFMul:
 			dst.move(i, lhs.Float(i) * rhs.Float(i));
 			break;
 		case spv::OpFDiv:
 			dst.move(i, lhs.Float(i) / rhs.Float(i));
 			break;
 		case spv::OpFMod:
 			// TODO(b/126873455): inaccurate for values greater than 2^24
 			dst.move(i, lhs.Float(i) - rhs.Float(i) * Floor(lhs.Float(i) / rhs.Float(i)));
 			break;
 		case spv::OpFRem:
 			dst.move(i, lhs.Float(i) % rhs.Float(i));
 			break;
 		case spv::OpFOrdEqual:
 			dst.move(i, CmpEQ(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFUnordEqual:
 			dst.move(i, CmpUEQ(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFOrdNotEqual:
 			dst.move(i, CmpNEQ(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFUnordNotEqual:
 			dst.move(i, CmpUNEQ(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFOrdLessThan:
 			dst.move(i, CmpLT(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFUnordLessThan:
 			dst.move(i, CmpULT(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFOrdGreaterThan:
 			dst.move(i, CmpGT(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFUnordGreaterThan:
 			dst.move(i, CmpUGT(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFOrdLessThanEqual:
 			dst.move(i, CmpLE(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFUnordLessThanEqual:
 			dst.move(i, CmpULE(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFOrdGreaterThanEqual:
 			dst.move(i, CmpGE(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpFUnordGreaterThanEqual:
 			dst.move(i, CmpUGE(lhs.Float(i), rhs.Float(i)));
 			break;
 		case spv::OpShiftRightLogical:
 			dst.move(i, lhs.UInt(i) >> rhs.UInt(i));
 			break;
 		case spv::OpShiftRightArithmetic:
 			dst.move(i, lhs.Int(i) >> rhs.Int(i));
 			break;
 		case spv::OpShiftLeftLogical:
 			dst.move(i, lhs.UInt(i) << rhs.UInt(i));
 			break;
 		case spv::OpBitwiseOr:
 		case spv::OpLogicalOr:
 			dst.move(i, lhs.UInt(i) | rhs.UInt(i));
 			break;
 		case spv::OpBitwiseXor:
 			dst.move(i, lhs.UInt(i) ^ rhs.UInt(i));
 			break;
 		case spv::OpBitwiseAnd:
 		case spv::OpLogicalAnd:
 			dst.move(i, lhs.UInt(i) & rhs.UInt(i));
 			break;
 		case spv::OpSMulExtended:
 			// Extended ops: result is a structure containing two members of the same type as lhs & rhs.
 			// In our flat view then, component i is the i'th component of the first member;
 			// component i + N is the i'th component of the second member.
 			dst.move(i, lhs.Int(i) * rhs.Int(i));
 			dst.move(i + lhsType.componentCount, MulHigh(lhs.Int(i), rhs.Int(i)));
 			break;
 		case spv::OpUMulExtended:
 			dst.move(i, lhs.UInt(i) * rhs.UInt(i));
 			dst.move(i + lhsType.componentCount, MulHigh(lhs.UInt(i), rhs.UInt(i)));
 			break;
 		case spv::OpIAddCarry:
 			dst.move(i, lhs.UInt(i) + rhs.UInt(i));
 			dst.move(i + lhsType.componentCount, CmpLT(dst.UInt(i), lhs.UInt(i)) >> 31);
 			break;
 		case spv::OpISubBorrow:
 			dst.move(i, lhs.UInt(i) - rhs.UInt(i));
 			dst.move(i + lhsType.componentCount, CmpLT(lhs.UInt(i), rhs.UInt(i)) >> 31);
 			break;
 		default:
 			UNREACHABLE("%s", OpcodeName(insn.opcode()));
 		}
 	}

 	SPIRV_SHADER_DBG("{0}: {1}", insn.word(2), dst);
 	SPIRV_SHADER_DBG("{0}: {1}", insn.word(3), lhs);
 	SPIRV_SHADER_DBG("{0}: {1}", insn.word(4), rhs);

 	return EmitResult::Continue;
 }

 SpirvShader::EmitResult SpirvShader::EmitDot(InsnIterator insn, EmitState *state) const
 {
 	auto &type = getType(insn.resultTypeId());
 	ASSERT(type.componentCount == 1);
 	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
 	auto &lhsType = getObjectType(insn.word(3));
 	auto lhs = Operand(this, state, insn.word(3));
 	auto rhs = Operand(this, state, insn.word(4));

 	dst.move(0, Dot(lhsType.componentCount, lhs, rhs));

 	SPIRV_SHADER_DBG("{0}: {1}", insn.resultId(), dst);
 	SPIRV_SHADER_DBG("{0}: {1}", insn.word(3), lhs);
 	SPIRV_SHADER_DBG("{0}: {1}", insn.word(4), rhs);

 	return EmitResult::Continue;
 }

 SIMD::Float SpirvShader::Dot(unsigned numComponents, Operand const &x, Operand const &y) const
 {
 	SIMD::Float d = x.Float(0) * y.Float(0);

 	for(auto i = 1u; i < numComponents; i++)
 	{
 		d += x.Float(i) * y.Float(i);
 	}

 	return d;
 }

 std::pair<SIMD::Float, SIMD::Int> SpirvShader::Frexp(RValue<SIMD::Float> val) const
 {
 	// Assumes IEEE 754
 	auto v = As<SIMD::UInt>(val);
 	auto isNotZero = CmpNEQ(v & SIMD::UInt(0x7FFFFFFF), SIMD::UInt(0));
 	auto zeroSign = v & SIMD::UInt(0x80000000) & ~isNotZero;
 	auto significand = As<SIMD::Float>((((v & SIMD::UInt(0x807FFFFF)) | SIMD::UInt(0x3F000000)) & isNotZero) | zeroSign);
 	auto exponent = Exponent(val) & SIMD::Int(isNotZero);
 	return std::make_pair(significand, exponent);
 }

 }  // namespace sw
	// Copyright 2019 The SwiftShader Authors. All Rights Reserved.
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	#include "SpirvShader.hpp"
	#include "SpirvShaderDebug.hpp"

	#include "ShaderCore.hpp"

	#include <spirv/unified1/spirv.hpp>

	namespace sw {

	SpirvShader::EmitResult SpirvShader::EmitVectorTimesScalar(InsnIterator insn, EmitState *state) const
	{
	auto &type = getType(insn.resultTypeId());
	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
	auto lhs = Operand(this, state, insn.word(3));
	auto rhs = Operand(this, state, insn.word(4));

	for(auto i = 0u; i < type.componentCount; i++)
	{
	dst.move(i, lhs.Float(i) * rhs.Float(0));
	}

	return EmitResult::Continue;
	}

	SpirvShader::EmitResult SpirvShader::EmitMatrixTimesVector(InsnIterator insn, EmitState *state) const
	{
	auto &type = getType(insn.resultTypeId());
	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
	auto lhs = Operand(this, state, insn.word(3));
	auto rhs = Operand(this, state, insn.word(4));

	for(auto i = 0u; i < type.componentCount; i++)
	{
	SIMD::Float v = lhs.Float(i) * rhs.Float(0);
	for(auto j = 1u; j < rhs.componentCount; j++)
	{
	v += lhs.Float(i + type.componentCount * j) * rhs.Float(j);
	}
	dst.move(i, v);
	}

	return EmitResult::Continue;
	}

	SpirvShader::EmitResult SpirvShader::EmitVectorTimesMatrix(InsnIterator insn, EmitState *state) const
	{
	auto &type = getType(insn.resultTypeId());
	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
	auto lhs = Operand(this, state, insn.word(3));
	auto rhs = Operand(this, state, insn.word(4));

	for(auto i = 0u; i < type.componentCount; i++)
	{
	SIMD::Float v = lhs.Float(0) * rhs.Float(i * lhs.componentCount);
	for(auto j = 1u; j < lhs.componentCount; j++)
	{
	v += lhs.Float(j) * rhs.Float(i * lhs.componentCount + j);
	}
	dst.move(i, v);
	}

	return EmitResult::Continue;
	}

	SpirvShader::EmitResult SpirvShader::EmitMatrixTimesMatrix(InsnIterator insn, EmitState *state) const
	{
	auto &type = getType(insn.resultTypeId());
	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
	auto lhs = Operand(this, state, insn.word(3));
	auto rhs = Operand(this, state, insn.word(4));

	auto numColumns = type.definition.word(3);
	auto numRows = getType(type.definition.word(2)).definition.word(3);
	auto numAdds = getObjectType(insn.word(3)).definition.word(3);

	for(auto row = 0u; row < numRows; row++)
	{
	for(auto col = 0u; col < numColumns; col++)
	{
	SIMD::Float v = SIMD::Float(0);
	for(auto i = 0u; i < numAdds; i++)
	{
	v += lhs.Float(i * numRows + row) * rhs.Float(col * numAdds + i);
	}
	dst.move(numRows * col + row, v);
	}
	}

	return EmitResult::Continue;
	}

	SpirvShader::EmitResult SpirvShader::EmitOuterProduct(InsnIterator insn, EmitState *state) const
	{
	auto &type = getType(insn.resultTypeId());
	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
	auto lhs = Operand(this, state, insn.word(3));
	auto rhs = Operand(this, state, insn.word(4));

	auto numRows = lhs.componentCount;
	auto numCols = rhs.componentCount;

	for(auto col = 0u; col < numCols; col++)
	{
	for(auto row = 0u; row < numRows; row++)
	{
	dst.move(col * numRows + row, lhs.Float(row) * rhs.Float(col));
	}
	}

	return EmitResult::Continue;
	}

	SpirvShader::EmitResult SpirvShader::EmitTranspose(InsnIterator insn, EmitState *state) const
	{
	auto &type = getType(insn.resultTypeId());
	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
	auto mat = Operand(this, state, insn.word(3));

	auto numCols = type.definition.word(3);
	auto numRows = getType(type.definition.word(2)).componentCount;

	for(auto col = 0u; col < numCols; col++)
	{
	for(auto row = 0u; row < numRows; row++)
	{
	dst.move(col * numRows + row, mat.Float(row * numCols + col));
	}
	}

	return EmitResult::Continue;
	}

	SpirvShader::EmitResult SpirvShader::EmitUnaryOp(InsnIterator insn, EmitState *state) const
	{
	auto &type = getType(insn.resultTypeId());
	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
	auto src = Operand(this, state, insn.word(3));

	for(auto i = 0u; i < type.componentCount; i++)
	{
	switch(insn.opcode())
	{
	case spv::OpNot:
	case spv::OpLogicalNot: // logical not == bitwise not due to all-bits boolean representation
	dst.move(i, ~src.UInt(i));
	break;
	case spv::OpBitFieldInsert:
	{
	auto insert = Operand(this, state, insn.word(4)).UInt(i);
	auto offset = Operand(this, state, insn.word(5)).UInt(0);
	auto count = Operand(this, state, insn.word(6)).UInt(0);
	auto one = SIMD::UInt(1);
	auto v = src.UInt(i);
	auto mask = Bitmask32(offset + count) ^ Bitmask32(offset);
	dst.move(i, (v & ~mask) \| ((insert << offset) & mask));
	}
	break;
	case spv::OpBitFieldSExtract:
	case spv::OpBitFieldUExtract:
	{
	auto offset = Operand(this, state, insn.word(4)).UInt(0);
	auto count = Operand(this, state, insn.word(5)).UInt(0);
	auto one = SIMD::UInt(1);
	auto v = src.UInt(i);
	SIMD::UInt out = (v >> offset) & Bitmask32(count);
	if(insn.opcode() == spv::OpBitFieldSExtract)
	{
	auto sign = out & NthBit32(count - one);
	auto sext = ~(sign - one);
	out \|= sext;
	}
	dst.move(i, out);
	}
	break;
	case spv::OpBitReverse:
	{
	// TODO: Add an intrinsic to reactor. Even if there isn't a
	// single vector instruction, there may be target-dependent
	// ways to make this faster.
	// https://graphics.stanford.edu/~seander/bithacks.html#ReverseParallel
	SIMD::UInt v = src.UInt(i);
	v = ((v >> 1) & SIMD::UInt(0x55555555)) \| ((v & SIMD::UInt(0x55555555)) << 1);
	v = ((v >> 2) & SIMD::UInt(0x33333333)) \| ((v & SIMD::UInt(0x33333333)) << 2);
	v = ((v >> 4) & SIMD::UInt(0x0F0F0F0F)) \| ((v & SIMD::UInt(0x0F0F0F0F)) << 4);
	v = ((v >> 8) & SIMD::UInt(0x00FF00FF)) \| ((v & SIMD::UInt(0x00FF00FF)) << 8);
	v = (v >> 16) \| (v << 16);
	dst.move(i, v);
	}
	break;
	case spv::OpBitCount:
	dst.move(i, CountBits(src.UInt(i)));
	break;
	case spv::OpSNegate:
	dst.move(i, -src.Int(i));
	break;
	case spv::OpFNegate:
	dst.move(i, -src.Float(i));
	break;
	case spv::OpConvertFToU:
	dst.move(i, SIMD::UInt(src.Float(i)));
	break;
	case spv::OpConvertFToS:
	dst.move(i, SIMD::Int(src.Float(i)));
	break;
	case spv::OpConvertSToF:
	dst.move(i, SIMD::Float(src.Int(i)));
	break;
	case spv::OpConvertUToF:
	dst.move(i, SIMD::Float(src.UInt(i)));
	break;
	case spv::OpBitcast:
	dst.move(i, src.Float(i));
	break;
	case spv::OpIsInf:
	dst.move(i, IsInf(src.Float(i)));
	break;
	case spv::OpIsNan:
	dst.move(i, IsNan(src.Float(i)));
	break;
	case spv::OpDPdx:
	case spv::OpDPdxCoarse:
	// Derivative instructions: FS invocations are laid out like so:
	// 0 1
	// 2 3
	static_assert(SIMD::Width == 4, "All cross-lane instructions will need care when using a different width");
	dst.move(i, SIMD::Float(Extract(src.Float(i), 1) - Extract(src.Float(i), 0)));
	break;
	case spv::OpDPdy:
	case spv::OpDPdyCoarse:
	dst.move(i, SIMD::Float(Extract(src.Float(i), 2) - Extract(src.Float(i), 0)));
	break;
	case spv::OpFwidth:
	case spv::OpFwidthCoarse:
	dst.move(i, SIMD::Float(Abs(Extract(src.Float(i), 1) - Extract(src.Float(i), 0)) + Abs(Extract(src.Float(i), 2) - Extract(src.Float(i), 0))));
	break;
	case spv::OpDPdxFine:
	{
	auto firstRow = Extract(src.Float(i), 1) - Extract(src.Float(i), 0);
	auto secondRow = Extract(src.Float(i), 3) - Extract(src.Float(i), 2);
	SIMD::Float v = SIMD::Float(firstRow);
	v = Insert(v, secondRow, 2);
	v = Insert(v, secondRow, 3);
	dst.move(i, v);
	}
	break;
	case spv::OpDPdyFine:
	{
	auto firstColumn = Extract(src.Float(i), 2) - Extract(src.Float(i), 0);
	auto secondColumn = Extract(src.Float(i), 3) - Extract(src.Float(i), 1);
	SIMD::Float v = SIMD::Float(firstColumn);
	v = Insert(v, secondColumn, 1);
	v = Insert(v, secondColumn, 3);
	dst.move(i, v);
	}
	break;
	case spv::OpFwidthFine:
	{
	auto firstRow = Extract(src.Float(i), 1) - Extract(src.Float(i), 0);
	auto secondRow = Extract(src.Float(i), 3) - Extract(src.Float(i), 2);
	SIMD::Float dpdx = SIMD::Float(firstRow);
	dpdx = Insert(dpdx, secondRow, 2);
	dpdx = Insert(dpdx, secondRow, 3);
	auto firstColumn = Extract(src.Float(i), 2) - Extract(src.Float(i), 0);
	auto secondColumn = Extract(src.Float(i), 3) - Extract(src.Float(i), 1);
	SIMD::Float dpdy = SIMD::Float(firstColumn);
	dpdy = Insert(dpdy, secondColumn, 1);
	dpdy = Insert(dpdy, secondColumn, 3);
	dst.move(i, Abs(dpdx) + Abs(dpdy));
	}
	break;
	case spv::OpQuantizeToF16:
	{
	// Note: keep in sync with the specialization constant version in EvalSpecConstantUnaryOp
	auto abs = Abs(src.Float(i));
	auto sign = src.Int(i) & SIMD::Int(0x80000000);
	auto isZero = CmpLT(abs, SIMD::Float(0.000061035f));
	auto isInf = CmpGT(abs, SIMD::Float(65504.0f));
	auto isNaN = IsNan(abs);
	auto isInfOrNan = isInf \| isNaN;
	SIMD::Int v = src.Int(i) & SIMD::Int(0xFFFFE000);
	v &= ~isZero \| SIMD::Int(0x80000000);
	v = sign \| (isInfOrNan & SIMD::Int(0x7F800000)) \| (~isInfOrNan & v);
	v \|= isNaN & SIMD::Int(0x400000);
	dst.move(i, v);
	}
	break;
	default:
	UNREACHABLE("%s", OpcodeName(insn.opcode()));
	}
	}

	return EmitResult::Continue;
	}

	SpirvShader::EmitResult SpirvShader::EmitBinaryOp(InsnIterator insn, EmitState *state) const
	{
	auto &type = getType(insn.resultTypeId());
	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
	auto &lhsType = getObjectType(insn.word(3));
	auto lhs = Operand(this, state, insn.word(3));
	auto rhs = Operand(this, state, insn.word(4));

	for(auto i = 0u; i < lhsType.componentCount; i++)
	{
	switch(insn.opcode())
	{
	case spv::OpIAdd:
	dst.move(i, lhs.Int(i) + rhs.Int(i));
	break;
	case spv::OpISub:
	dst.move(i, lhs.Int(i) - rhs.Int(i));
	break;
	case spv::OpIMul:
	dst.move(i, lhs.Int(i) * rhs.Int(i));
	break;
	case spv::OpSDiv:
	{
	SIMD::Int a = lhs.Int(i);
	SIMD::Int b = rhs.Int(i);
	b = b \| CmpEQ(b, SIMD::Int(0)); // prevent divide-by-zero
	a = a \| (CmpEQ(a, SIMD::Int(0x80000000)) & CmpEQ(b, SIMD::Int(-1))); // prevent integer overflow
	dst.move(i, a / b);
	}
	break;
	case spv::OpUDiv:
	{
	auto zeroMask = As<SIMD::UInt>(CmpEQ(rhs.Int(i), SIMD::Int(0)));
	dst.move(i, lhs.UInt(i) / (rhs.UInt(i) \| zeroMask));
	}
	break;
	case spv::OpSRem:
	{
	SIMD::Int a = lhs.Int(i);
	SIMD::Int b = rhs.Int(i);
	b = b \| CmpEQ(b, SIMD::Int(0)); // prevent divide-by-zero
	a = a \| (CmpEQ(a, SIMD::Int(0x80000000)) & CmpEQ(b, SIMD::Int(-1))); // prevent integer overflow
	dst.move(i, a % b);
	}
	break;
	case spv::OpSMod:
	{
	SIMD::Int a = lhs.Int(i);
	SIMD::Int b = rhs.Int(i);
	b = b \| CmpEQ(b, SIMD::Int(0)); // prevent divide-by-zero
	a = a \| (CmpEQ(a, SIMD::Int(0x80000000)) & CmpEQ(b, SIMD::Int(-1))); // prevent integer overflow
	auto mod = a % b;
	// If a and b have opposite signs, the remainder operation takes
	// the sign from a but OpSMod is supposed to take the sign of b.
	// Adding b will ensure that the result has the correct sign and
	// that it is still congruent to a modulo b.
	//
	// See also http://mathforum.org/library/drmath/view/52343.html
	auto signDiff = CmpNEQ(CmpGE(a, SIMD::Int(0)), CmpGE(b, SIMD::Int(0)));
	auto fixedMod = mod + (b & CmpNEQ(mod, SIMD::Int(0)) & signDiff);
	dst.move(i, As<SIMD::Float>(fixedMod));
	}
	break;
	case spv::OpUMod:
	{
	auto zeroMask = As<SIMD::UInt>(CmpEQ(rhs.Int(i), SIMD::Int(0)));
	dst.move(i, lhs.UInt(i) % (rhs.UInt(i) \| zeroMask));
	}
	break;
	case spv::OpIEqual:
	case spv::OpLogicalEqual:
	dst.move(i, CmpEQ(lhs.Int(i), rhs.Int(i)));
	break;
	case spv::OpINotEqual:
	case spv::OpLogicalNotEqual:
	dst.move(i, CmpNEQ(lhs.Int(i), rhs.Int(i)));
	break;
	case spv::OpUGreaterThan:
	dst.move(i, CmpGT(lhs.UInt(i), rhs.UInt(i)));
	break;
	case spv::OpSGreaterThan:
	dst.move(i, CmpGT(lhs.Int(i), rhs.Int(i)));
	break;
	case spv::OpUGreaterThanEqual:
	dst.move(i, CmpGE(lhs.UInt(i), rhs.UInt(i)));
	break;
	case spv::OpSGreaterThanEqual:
	dst.move(i, CmpGE(lhs.Int(i), rhs.Int(i)));
	break;
	case spv::OpULessThan:
	dst.move(i, CmpLT(lhs.UInt(i), rhs.UInt(i)));
	break;
	case spv::OpSLessThan:
	dst.move(i, CmpLT(lhs.Int(i), rhs.Int(i)));
	break;
	case spv::OpULessThanEqual:
	dst.move(i, CmpLE(lhs.UInt(i), rhs.UInt(i)));
	break;
	case spv::OpSLessThanEqual:
	dst.move(i, CmpLE(lhs.Int(i), rhs.Int(i)));
	break;
	case spv::OpFAdd:
	dst.move(i, lhs.Float(i) + rhs.Float(i));
	break;
	case spv::OpFSub:
	dst.move(i, lhs.Float(i) - rhs.Float(i));
	break;
	case spv::OpFMul:
	dst.move(i, lhs.Float(i) * rhs.Float(i));
	break;
	case spv::OpFDiv:
	dst.move(i, lhs.Float(i) / rhs.Float(i));
	break;
	case spv::OpFMod:
	// TODO(b/126873455): inaccurate for values greater than 2^24
	dst.move(i, lhs.Float(i) - rhs.Float(i) * Floor(lhs.Float(i) / rhs.Float(i)));
	break;
	case spv::OpFRem:
	dst.move(i, lhs.Float(i) % rhs.Float(i));
	break;
	case spv::OpFOrdEqual:
	dst.move(i, CmpEQ(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFUnordEqual:
	dst.move(i, CmpUEQ(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFOrdNotEqual:
	dst.move(i, CmpNEQ(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFUnordNotEqual:
	dst.move(i, CmpUNEQ(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFOrdLessThan:
	dst.move(i, CmpLT(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFUnordLessThan:
	dst.move(i, CmpULT(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFOrdGreaterThan:
	dst.move(i, CmpGT(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFUnordGreaterThan:
	dst.move(i, CmpUGT(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFOrdLessThanEqual:
	dst.move(i, CmpLE(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFUnordLessThanEqual:
	dst.move(i, CmpULE(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFOrdGreaterThanEqual:
	dst.move(i, CmpGE(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpFUnordGreaterThanEqual:
	dst.move(i, CmpUGE(lhs.Float(i), rhs.Float(i)));
	break;
	case spv::OpShiftRightLogical:
	dst.move(i, lhs.UInt(i) >> rhs.UInt(i));
	break;
	case spv::OpShiftRightArithmetic:
	dst.move(i, lhs.Int(i) >> rhs.Int(i));
	break;
	case spv::OpShiftLeftLogical:
	dst.move(i, lhs.UInt(i) << rhs.UInt(i));
	break;
	case spv::OpBitwiseOr:
	case spv::OpLogicalOr:
	dst.move(i, lhs.UInt(i) \| rhs.UInt(i));
	break;
	case spv::OpBitwiseXor:
	dst.move(i, lhs.UInt(i) ^ rhs.UInt(i));
	break;
	case spv::OpBitwiseAnd:
	case spv::OpLogicalAnd:
	dst.move(i, lhs.UInt(i) & rhs.UInt(i));
	break;
	case spv::OpSMulExtended:
	// Extended ops: result is a structure containing two members of the same type as lhs & rhs.
	// In our flat view then, component i is the i'th component of the first member;
	// component i + N is the i'th component of the second member.
	dst.move(i, lhs.Int(i) * rhs.Int(i));
	dst.move(i + lhsType.componentCount, MulHigh(lhs.Int(i), rhs.Int(i)));
	break;
	case spv::OpUMulExtended:
	dst.move(i, lhs.UInt(i) * rhs.UInt(i));
	dst.move(i + lhsType.componentCount, MulHigh(lhs.UInt(i), rhs.UInt(i)));
	break;
	case spv::OpIAddCarry:
	dst.move(i, lhs.UInt(i) + rhs.UInt(i));
	dst.move(i + lhsType.componentCount, CmpLT(dst.UInt(i), lhs.UInt(i)) >> 31);
	break;
	case spv::OpISubBorrow:
	dst.move(i, lhs.UInt(i) - rhs.UInt(i));
	dst.move(i + lhsType.componentCount, CmpLT(lhs.UInt(i), rhs.UInt(i)) >> 31);
	break;
	default:
	UNREACHABLE("%s", OpcodeName(insn.opcode()));
	}
	}

	SPIRV_SHADER_DBG("{0}: {1}", insn.word(2), dst);
	SPIRV_SHADER_DBG("{0}: {1}", insn.word(3), lhs);
	SPIRV_SHADER_DBG("{0}: {1}", insn.word(4), rhs);

	return EmitResult::Continue;
	}

	SpirvShader::EmitResult SpirvShader::EmitDot(InsnIterator insn, EmitState *state) const
	{
	auto &type = getType(insn.resultTypeId());
	ASSERT(type.componentCount == 1);
	auto &dst = state->createIntermediate(insn.resultId(), type.componentCount);
	auto &lhsType = getObjectType(insn.word(3));
	auto lhs = Operand(this, state, insn.word(3));
	auto rhs = Operand(this, state, insn.word(4));

	dst.move(0, Dot(lhsType.componentCount, lhs, rhs));

	SPIRV_SHADER_DBG("{0}: {1}", insn.resultId(), dst);
	SPIRV_SHADER_DBG("{0}: {1}", insn.word(3), lhs);
	SPIRV_SHADER_DBG("{0}: {1}", insn.word(4), rhs);

	return EmitResult::Continue;
	}

	SIMD::Float SpirvShader::Dot(unsigned numComponents, Operand const &x, Operand const &y) const
	{
	SIMD::Float d = x.Float(0) * y.Float(0);

	for(auto i = 1u; i < numComponents; i++)
	{
	d += x.Float(i) * y.Float(i);
	}

	return d;
	}

	std::pair<SIMD::Float, SIMD::Int> SpirvShader::Frexp(RValue<SIMD::Float> val) const
	{
	// Assumes IEEE 754
	auto v = As<SIMD::UInt>(val);
	auto isNotZero = CmpNEQ(v & SIMD::UInt(0x7FFFFFFF), SIMD::UInt(0));
	auto zeroSign = v & SIMD::UInt(0x80000000) & ~isNotZero;
	auto significand = As<SIMD::Float>((((v & SIMD::UInt(0x807FFFFF)) \| SIMD::UInt(0x3F000000)) & isNotZero) \| zeroSign);
	auto exponent = Exponent(val) & SIMD::Int(isNotZero);
	return std::make_pair(significand, exponent);
	}

	} // namespace sw