mirror of
https://git.h3cjp.net/H3cJP/yuzu.git
synced 2024-12-14 14:55:39 +00:00
shader_jit_x64: Rewrite flow control to support arbitrary CALL and JMP instructions.
This commit is contained in:
bunnei
parent
135aec7bea
commit
4632791a40
|
|
@ -137,6 +137,15 @@ static const u8 NO_SRC_REG_SWIZZLE = 0x1b;
|
|||
/// Raw constant for the destination register enable mask that indicates all components are enabled
|
||||
static const u8 NO_DEST_REG_MASK = 0xf;
|
||||
|
||||
/**
|
||||
* Get the vertex shader instruction for a given offset in the current shader program
|
||||
* @param offset Offset in the current shader program of the instruction
|
||||
* @return Instruction at the specified offset
|
||||
*/
|
||||
static Instruction GetVertexShaderInstruction(size_t offset) {
|
||||
return { g_state.vs.program_code[offset] };
|
||||
}
|
||||
|
||||
/**
|
||||
* Loads and swizzles a source register into the specified XMM register.
|
||||
* @param instr VS instruction, used for determining how to load the source register
|
||||
|
|
@ -564,10 +573,23 @@ void JitCompiler::Compile_END(Instruction instr) {
|
|||
}
|
||||
|
||||
void JitCompiler::Compile_CALL(Instruction instr) {
|
||||
unsigned offset = instr.flow_control.dest_offset;
|
||||
while (offset < (instr.flow_control.dest_offset + instr.flow_control.num_instructions)) {
|
||||
Compile_NextInstr(&offset);
|
||||
}
|
||||
// Need to advance the return address past the proceeding instructions, this is the number of bytes to skip
|
||||
constexpr unsigned SKIP = 21;
|
||||
const uintptr_t start = reinterpret_cast<uintptr_t>(GetCodePtr());
|
||||
|
||||
// Push return address - not using CALL because we also want to push the offset of the return before jumping
|
||||
MOV(64, R(RAX), ImmPtr(GetCodePtr() + SKIP));
|
||||
PUSH(RAX);
|
||||
|
||||
// Push offset of the return
|
||||
PUSH(32, Imm32(instr.flow_control.dest_offset + instr.flow_control.num_instructions));
|
||||
|
||||
// Jump
|
||||
FixupBranch b = J(true);
|
||||
fixup_branches.push_back({ b, instr.flow_control.dest_offset });
|
||||
|
||||
// Make sure that if the above code changes, SKIP gets updated
|
||||
ASSERT(reinterpret_cast<uintptr_t>(GetCodePtr()) - start == SKIP);
|
||||
}
|
||||
|
||||
void JitCompiler::Compile_CALLC(Instruction instr) {
|
||||
|
|
@ -645,8 +667,8 @@ void JitCompiler::Compile_MAD(Instruction instr) {
|
|||
}
|
||||
|
||||
void JitCompiler::Compile_IF(Instruction instr) {
|
||||
ASSERT_MSG(instr.flow_control.dest_offset > *offset_ptr, "Backwards if-statements (%d -> %d) not supported",
|
||||
*offset_ptr, instr.flow_control.dest_offset.Value());
|
||||
ASSERT_MSG(instr.flow_control.dest_offset > last_program_counter, "Backwards if-statements (%d -> %d) not supported",
|
||||
last_program_counter, instr.flow_control.dest_offset.Value());
|
||||
|
||||
// Evaluate the "IF" condition
|
||||
if (instr.opcode.Value() == OpCode::Id::IFU) {
|
||||
|
|
@ -677,8 +699,8 @@ void JitCompiler::Compile_IF(Instruction instr) {
|
|||
}
|
||||
|
||||
void JitCompiler::Compile_LOOP(Instruction instr) {
|
||||
ASSERT_MSG(instr.flow_control.dest_offset > *offset_ptr, "Backwards loops (%d -> %d) not supported",
|
||||
*offset_ptr, instr.flow_control.dest_offset.Value());
|
||||
ASSERT_MSG(instr.flow_control.dest_offset > last_program_counter, "Backwards loops (%d -> %d) not supported",
|
||||
last_program_counter, instr.flow_control.dest_offset.Value());
|
||||
ASSERT_MSG(!looping, "Nested loops not supported");
|
||||
|
||||
looping = true;
|
||||
|
|
@ -706,9 +728,6 @@ void JitCompiler::Compile_LOOP(Instruction instr) {
|
|||
}
|
||||
|
||||
void JitCompiler::Compile_JMP(Instruction instr) {
|
||||
ASSERT_MSG(instr.flow_control.dest_offset > *offset_ptr, "Backwards jumps (%d -> %d) not supported",
|
||||
*offset_ptr, instr.flow_control.dest_offset.Value());
|
||||
|
||||
if (instr.opcode.Value() == OpCode::Id::JMPC)
|
||||
Compile_EvaluateCondition(instr);
|
||||
else if (instr.opcode.Value() == OpCode::Id::JMPU)
|
||||
|
|
@ -718,31 +737,42 @@ void JitCompiler::Compile_JMP(Instruction instr) {
|
|||
|
||||
bool inverted_condition = (instr.opcode.Value() == OpCode::Id::JMPU) &&
|
||||
(instr.flow_control.num_instructions & 1);
|
||||
|
||||
FixupBranch b = J_CC(inverted_condition ? CC_Z : CC_NZ, true);
|
||||
|
||||
Compile_Block(instr.flow_control.dest_offset);
|
||||
|
||||
SetJumpTarget(b);
|
||||
fixup_branches.push_back({ b, instr.flow_control.dest_offset });
|
||||
}
|
||||
|
||||
void JitCompiler::Compile_Block(unsigned end) {
|
||||
// Save current offset pointer
|
||||
unsigned* prev_offset_ptr = offset_ptr;
|
||||
unsigned offset = *prev_offset_ptr;
|
||||
|
||||
while (offset < end)
|
||||
Compile_NextInstr(&offset);
|
||||
|
||||
// Restore current offset pointer
|
||||
offset_ptr = prev_offset_ptr;
|
||||
*offset_ptr = offset;
|
||||
while (program_counter < end) {
|
||||
Compile_NextInstr();
|
||||
}
|
||||
}
|
||||
|
||||
void JitCompiler::Compile_NextInstr(unsigned* offset) {
|
||||
offset_ptr = offset;
|
||||
void JitCompiler::Compile_Return() {
|
||||
// Peek return offset on the stack and check if we're at that offset
|
||||
MOV(64, R(RAX), MDisp(RSP, 0));
|
||||
CMP(32, R(RAX), Imm32(program_counter));
|
||||
|
||||
Instruction instr;
|
||||
std::memcpy(&instr, &g_state.vs.program_code[(*offset_ptr)++], sizeof(Instruction));
|
||||
// If so, jump back to before CALL
|
||||
FixupBranch b = J_CC(CC_NZ, true);
|
||||
ADD(64, R(RSP), Imm32(8)); // Ignore return offset that's on the stack
|
||||
POP(RAX); // Pop off return address
|
||||
JMPptr(R(RAX));
|
||||
SetJumpTarget(b);
|
||||
}
|
||||
|
||||
void JitCompiler::Compile_NextInstr() {
|
||||
last_program_counter = program_counter;
|
||||
|
||||
auto search = return_offsets.find(program_counter);
|
||||
if (search != return_offsets.end()) {
|
||||
Compile_Return();
|
||||
}
|
||||
|
||||
ASSERT_MSG(code_ptr[program_counter] == nullptr, "Tried to compile already compiled shader location!");
|
||||
code_ptr[program_counter] = GetCodePtr();
|
||||
|
||||
Instruction instr = GetVertexShaderInstruction(program_counter++);
|
||||
|
||||
OpCode::Id opcode = instr.opcode.Value();
|
||||
auto instr_func = instr_table[static_cast<unsigned>(opcode)];
|
||||
|
|
@ -757,9 +787,24 @@ void JitCompiler::Compile_NextInstr(unsigned* offset) {
|
|||
}
|
||||
}
|
||||
|
||||
void JitCompiler::FindReturnOffsets() {
|
||||
return_offsets.clear();
|
||||
|
||||
for (size_t offset = 0; offset < g_state.vs.program_code.size(); ++offset) {
|
||||
Instruction instr = GetVertexShaderInstruction(offset);
|
||||
|
||||
switch (instr.opcode.Value()) {
|
||||
case OpCode::Id::CALL:
|
||||
case OpCode::Id::CALLC:
|
||||
case OpCode::Id::CALLU:
|
||||
return_offsets.insert(instr.flow_control.dest_offset + instr.flow_control.num_instructions);
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
CompiledShader* JitCompiler::Compile() {
|
||||
const u8* start = GetCodePtr();
|
||||
unsigned offset = g_state.regs.vs.main_offset;
|
||||
|
||||
// The stack pointer is 8 modulo 16 at the entry of a procedure
|
||||
ABI_PushRegistersAndAdjustStack(ABI_ALL_CALLEE_SAVED, 8);
|
||||
|
|
@ -782,10 +827,27 @@ CompiledShader* JitCompiler::Compile() {
|
|||
MOV(PTRBITS, R(RAX), ImmPtr(&neg));
|
||||
MOVAPS(NEGBIT, MatR(RAX));
|
||||
|
||||
looping = false;
|
||||
// Find all `CALL` instructions and identify return locations
|
||||
FindReturnOffsets();
|
||||
|
||||
while (offset < g_state.vs.program_code.size()) {
|
||||
Compile_NextInstr(&offset);
|
||||
// Reset flow control state
|
||||
last_program_counter = 0;
|
||||
program_counter = 0;
|
||||
looping = false;
|
||||
code_ptr.fill(nullptr);
|
||||
fixup_branches.clear();
|
||||
|
||||
// Jump to start of the shader program
|
||||
if (g_state.regs.vs.main_offset != 0) {
|
||||
fixup_branches.push_back({ J(true), g_state.regs.vs.main_offset });
|
||||
}
|
||||
|
||||
// Compile entire program
|
||||
Compile_Block(static_cast<unsigned>(g_state.vs.program_code.size()));
|
||||
|
||||
// Set the target for any incomplete branches now that the entire shader program has been emitted
|
||||
for (const auto& branch : fixup_branches) {
|
||||
SetJumpTarget(branch.first, code_ptr[branch.second]);
|
||||
}
|
||||
|
||||
return (CompiledShader*)start;
|
||||
|
|
|
|||
|
|
@ -4,6 +4,9 @@
|
|||
|
||||
#pragma once
|
||||
|
||||
#include <set>
|
||||
#include <utility>
|
||||
|
||||
#include <nihstro/shader_bytecode.h>
|
||||
|
||||
#include "common/x64/emitter.h"
|
||||
|
|
@ -66,8 +69,9 @@ public:
|
|||
void Compile_MAD(Instruction instr);
|
||||
|
||||
private:
|
||||
|
||||
void Compile_Block(unsigned end);
|
||||
void Compile_NextInstr(unsigned* offset);
|
||||
void Compile_NextInstr();
|
||||
|
||||
void Compile_SwizzleSrc(Instruction instr, unsigned src_num, SourceRegister src_reg, Gen::X64Reg dest);
|
||||
void Compile_DestEnable(Instruction instr, Gen::X64Reg dest);
|
||||
|
|
@ -81,13 +85,31 @@ private:
|
|||
void Compile_EvaluateCondition(Instruction instr);
|
||||
void Compile_UniformCondition(Instruction instr);
|
||||
|
||||
/**
|
||||
* Emits the code to conditionally return from a subroutine envoked by the `CALL` instruction.
|
||||
*/
|
||||
void Compile_Return();
|
||||
|
||||
BitSet32 PersistentCallerSavedRegs();
|
||||
|
||||
/// Pointer to the variable that stores the current Pica code offset. Used to handle nested code blocks.
|
||||
unsigned* offset_ptr = nullptr;
|
||||
/**
|
||||
* Analyzes the entire shader program for `CALL` instructions before emitting any code,
|
||||
* identifying the locations where a return needs to be inserted.
|
||||
*/
|
||||
void FindReturnOffsets();
|
||||
|
||||
/// Set to true if currently in a loop, used to check for the existence of nested loops
|
||||
bool looping = false;
|
||||
/// Mapping of Pica VS instructions to pointers in the emitted code
|
||||
std::array<const u8*, 1024> code_ptr;
|
||||
|
||||
/// Offsets in code where a return needs to be inserted
|
||||
std::set<unsigned> return_offsets;
|
||||
|
||||
unsigned last_program_counter; ///< Offset of the most recent instruction decoded
|
||||
unsigned program_counter; ///< Offset of the next instruction to decode
|
||||
bool looping = false; ///< True if compiling a loop, used to check for nested loops
|
||||
|
||||
/// Branches that need to be fixed up once the entire shader program is compiled
|
||||
std::vector<std::pair<Gen::FixupBranch, unsigned>> fixup_branches;
|
||||
};
|
||||
|
||||
} // Shader
|
||||
|
|
|
|||
Loading…
Reference in a new issue