Merge pull request #3619 from ReinUsesLisp/i2i

shader/conversion: Implement I2I sign extension, saturation and selection
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Mat M 2020-04-13 10:17:07 -04:00 committed by GitHub
commit 7b62212461
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@ -2,6 +2,10 @@
// Licensed under GPLv2 or any later version // Licensed under GPLv2 or any later version
// Refer to the license.txt file included. // Refer to the license.txt file included.
#include <limits>
#include <optional>
#include <utility>
#include "common/assert.h" #include "common/assert.h"
#include "common/common_types.h" #include "common/common_types.h"
#include "video_core/engines/shader_bytecode.h" #include "video_core/engines/shader_bytecode.h"
@ -15,9 +19,49 @@ using Tegra::Shader::OpCode;
using Tegra::Shader::Register; using Tegra::Shader::Register;
namespace { namespace {
constexpr OperationCode GetFloatSelector(u64 selector) { constexpr OperationCode GetFloatSelector(u64 selector) {
return selector == 0 ? OperationCode::FCastHalf0 : OperationCode::FCastHalf1; return selector == 0 ? OperationCode::FCastHalf0 : OperationCode::FCastHalf1;
} }
constexpr u32 SizeInBits(Register::Size size) {
switch (size) {
case Register::Size::Byte:
return 8;
case Register::Size::Short:
return 16;
case Register::Size::Word:
return 32;
case Register::Size::Long:
return 64;
}
return 0;
}
constexpr std::optional<std::pair<s32, s32>> IntegerSaturateBounds(Register::Size src_size,
Register::Size dst_size,
bool src_signed,
bool dst_signed) {
const u32 dst_bits = SizeInBits(dst_size);
if (src_size == Register::Size::Word && dst_size == Register::Size::Word) {
if (src_signed == dst_signed) {
return std::nullopt;
}
return std::make_pair(0, std::numeric_limits<s32>::max());
}
if (dst_signed) {
// Signed destination, clamp to [-128, 127] for instance
return std::make_pair(-(1 << (dst_bits - 1)), (1 << (dst_bits - 1)) - 1);
} else {
// Unsigned destination
if (dst_bits == 32) {
// Avoid shifting by 32, that is undefined behavior
return std::make_pair(0, s32(std::numeric_limits<u32>::max()));
}
return std::make_pair(0, (1 << dst_bits) - 1);
}
}
} // Anonymous namespace } // Anonymous namespace
u32 ShaderIR::DecodeConversion(NodeBlock& bb, u32 pc) { u32 ShaderIR::DecodeConversion(NodeBlock& bb, u32 pc) {
@ -28,14 +72,13 @@ u32 ShaderIR::DecodeConversion(NodeBlock& bb, u32 pc) {
case OpCode::Id::I2I_R: case OpCode::Id::I2I_R:
case OpCode::Id::I2I_C: case OpCode::Id::I2I_C:
case OpCode::Id::I2I_IMM: { case OpCode::Id::I2I_IMM: {
UNIMPLEMENTED_IF(instr.conversion.int_src.selector != 0); const bool src_signed = instr.conversion.is_input_signed;
UNIMPLEMENTED_IF(instr.conversion.dst_size != Register::Size::Word); const bool dst_signed = instr.conversion.is_output_signed;
UNIMPLEMENTED_IF(instr.alu.saturate_d); const Register::Size src_size = instr.conversion.src_size;
const Register::Size dst_size = instr.conversion.dst_size;
const u32 selector = static_cast<u32>(instr.conversion.int_src.selector);
const bool input_signed = instr.conversion.is_input_signed; Node value = [this, instr, opcode] {
const bool output_signed = instr.conversion.is_output_signed;
Node value = [&]() {
switch (opcode->get().GetId()) { switch (opcode->get().GetId()) {
case OpCode::Id::I2I_R: case OpCode::Id::I2I_R:
return GetRegister(instr.gpr20); return GetRegister(instr.gpr20);
@ -48,16 +91,60 @@ u32 ShaderIR::DecodeConversion(NodeBlock& bb, u32 pc) {
return Immediate(0); return Immediate(0);
} }
}(); }();
value = ConvertIntegerSize(value, instr.conversion.src_size, input_signed);
value = GetOperandAbsNegInteger(value, instr.conversion.abs_a, instr.conversion.negate_a, // Ensure the source selector is valid
input_signed); switch (instr.conversion.src_size) {
if (input_signed != output_signed) { case Register::Size::Byte:
value = SignedOperation(OperationCode::ICastUnsigned, output_signed, NO_PRECISE, value); break;
case Register::Size::Short:
ASSERT(selector == 0 || selector == 2);
break;
default:
ASSERT(selector == 0);
break;
}
if (src_size != Register::Size::Word || selector != 0) {
value = SignedOperation(OperationCode::IBitfieldExtract, src_signed, std::move(value),
Immediate(selector * 8), Immediate(SizeInBits(src_size)));
}
value = GetOperandAbsNegInteger(std::move(value), instr.conversion.abs_a,
instr.conversion.negate_a, src_signed);
if (instr.alu.saturate_d) {
if (src_signed && !dst_signed) {
Node is_negative = Operation(OperationCode::LogicalUGreaterEqual, value,
Immediate(1 << (SizeInBits(src_size) - 1)));
value = Operation(OperationCode::Select, std::move(is_negative), Immediate(0),
std::move(value));
// Simplify generated expressions, this can be removed without semantic impact
SetTemporary(bb, 0, std::move(value));
value = GetTemporary(0);
if (dst_size != Register::Size::Word) {
const Node limit = Immediate((1 << SizeInBits(dst_size)) - 1);
Node is_large =
Operation(OperationCode::LogicalUGreaterThan, std::move(value), limit);
value = Operation(OperationCode::Select, std::move(is_large), limit,
std::move(value));
}
} else if (const std::optional bounds =
IntegerSaturateBounds(src_size, dst_size, src_signed, dst_signed)) {
value = SignedOperation(OperationCode::IMax, src_signed, std::move(value),
Immediate(bounds->first));
value = SignedOperation(OperationCode::IMin, src_signed, std::move(value),
Immediate(bounds->second));
}
} else if (dst_size != Register::Size::Word) {
// No saturation, we only have to mask the result
Node mask = Immediate((1 << SizeInBits(dst_size)) - 1);
value = Operation(OperationCode::UBitwiseAnd, std::move(value), std::move(mask));
} }
SetInternalFlagsFromInteger(bb, value, instr.generates_cc); SetInternalFlagsFromInteger(bb, value, instr.generates_cc);
SetRegister(bb, instr.gpr0, value); SetRegister(bb, instr.gpr0, std::move(value));
break; break;
} }
case OpCode::Id::I2F_R: case OpCode::Id::I2F_R: