Add alternate path to DOT_PRODUCT_3/4 for use_fast_dot_product that skips all the status register stuff and just remaps inf to qnan
Add OPCODE_TO_SINGLE to replace the CONVERT_F32_F64 - CONVERT_F64_F32 sequence we used to emit with the idea that a backend could implement a more correct rounding behavior if possible on its arch
Remove some impossible sequences like MUL_HI_I8/I16, MUL_ADD_F32, DIV_V128. These instructions have no equivalent in PPC. Many other instructions are unused/dead code and should be removed to make the x64 backend a better reference for future ones
Add backend_flags to Instr. Basically, flags field that a backend can use for whatever it wants when generating code.
Add backend instr flag to x64 that tells it to not generate code for an instruction. this allows sequences to consume subsequent instructions
Generate actual x64 code for VSL instruction instead of using callnativesafe
Detect repeated COMPARE instructions w/ identical operands and reuse the results in FLAGS if so. this eliminates a ton of garbage compare/set instructions.
If a COMPARE instructions destination is stored to context with no intervening instruction and no additional uses besides the store, do setx [ctx address]
Detect prefetchw and use it in CACHE_CONTROL if prefetch for write is requested instead of doing prefetch to all cache levels
Fixed an accident in an earlier commit by me, VECTOR_DENORMFLUSH was not being emitted at all, so denormal inputs to MUL_ADD_V128 were not becoming zero and outputs from DOT_PRODUCT_X were not either. I believe this introduced a bug into RDR where a wagon wouldnt spawn? (https://discord.com/channels/308194948048486401/308207592482668545/1000443975817252874)
Compute fresx in double precision using RECIP_F64 and then round to single instead of doing (double)(1.0f / (float)value), matching original behavior better
Refactor some of ppc_emit_fpu, much of the InstrEmit function are identical except for whether they round to single or not
Added "tail emitters" to X64Emitter. These are callbacks that get invoked with their label and the X64Emitter after the epilog code. This allows us to move cold code out of the critical path and in the future place constant pools near functions
guest_to_host_thunk/host_to_guest_thunk now gets directly rel32 called, instead of doing a mov
Add X64BackendContext structure, represents data before the start of the PPCContext
Instead of doing branchless sequence, do a compare and jump to tail emitted code for address translation. This makes converting addresses a 3 uop affair in most cases.
Do qnan move for dot product in a tail emitter
Detect whether EFLAGS bits are independent variables for the current cpu (not really detecting it ehe, just checking if zen) and if so generate inc/dec for add/sub 1
Detect whether low 32 bits of membase are 0. If they are then we can use membasereg.cvt32() in place of immediate 0 in many places, particularly in stores
Detect LOAD MODIFY STORE pattern for context variables (currently only done for 64 bit ones) and turn them into modify [context ptr]. This is done for add, sub, and, or, xor, not, neg
Tail emit error handling for TRAP opcodes
Stub out unused trap opcodes like TRAP_TRUE_I32, TRAP_TRUE_I64, TRAP_TRUE_I16 (the call_true/return_true opcodes for these types are also probably unused)
Remove BackpropTruncations. It was poorly written and causes crashes on the game Viva pinata (https://discord.com/channels/308194948048486401/701111856600711208/1000249460451983420)
Use variable for Python version to make upgrading easier.
xb.bat:
Update copyright date.
Add candidate paths.
xb.ps1
Properly use found python executable.
More consistency with .bat.
Don't spew unnecessary errors, etc.
EOF newline.
For more optimal usage of exports and the parameter cache on the host regardless of how effective the optimizations in the host GPU driver are. Also reserve space for Vulkan/Metal/D3D11-specific HostVertexShaderTypes to use one more bit for the host vertex shader type in the shader modification bits, so that won't have to be done in the future as that would require invalidating shader storages (which are invalidated by this commit) again.
Use shuffle_ps instead of broadcastss, broadcastss is slower on many intel and amd processors and encodes to the same number of bytes as shuffle_ps
Detect and optimize away PERMUTE with a zero src2 and src3 in constant_propagation_pass instead of in the x64 sequence
For constant PERMUTE, do the Xor/And prior to LoadConstantXmm instead of in the generated code
Simplified code for PERMUTE
Added simplification rule that detects (lzcnt(x) >> log2(bitsizeof_x)) == ( x == 0)
Added set_srcN(value, idx) which can be used to set the nth source of an instruction, which makes more sense than having three different functions that only differ by the field they touch
Added Value::VisitValueOperands for iterating all Value operands an instruction has.
Add BackpropTruncations code to simplification_pass
Changed the (void**) dereferences of raw_context that are done to grab thread_state to instead reference PPCContext and the thread_state field. Moved the thread_state field to the tail of PPCContext.
Moved membase to the tail of PPCContext, since now it is reloaded very infrequently.
Rearranged PPCContext so that the condition registers come first (most accesses to them cant get SSA'd), moved lr and ctr to after gp regs since they are not accessed as much as the main gpregs. This way the most frequently
accessed registers will be accessible via a rel8 displacement instead of rel32 (ideally, we would have only certain CRs at the start, but xenia does pointer arithmetic on CR0's offset to get CRn)
Use alignas(64) to ensure PPCContext's padding
Map PPCContext specially so that the low 32 bits of the context register is 0xE0000000, for the 4k page offset check. Also allocate the page before, so that backends can store their own information that is not relevant to the PPCContext on that page and
reference that data in the generated asm via 8-bit signed displ or 32-bit signed displ. Currently this page is not being utilized, but I plan on stashing some data critical to the x86 backend there
Changed many wrong avx instructions, they worked but they were not intended for the data they operated on, meaning they transferred domains and caused 1-2 cycle stall each time
Added SimdDomain checking/deduction to X64Emitter.
Used SimdDomain code to fix a lot of float/int domain stalls
Use the low 32 bits of the context register instead of constant 0xE0000000 in ComputeAddress
Special path for SELECT_V128 with result of comparison that will use a blend instruction instead of and/or
Many HIR optimizations added in simp pass
A bunch of other stuff running out of time to write this msg
GPU traces in the trace viewer are accessed via the Storage Access Framework, which doesn't require the storage permissions. Games will be accessed using the SAF too (directories containing games as document trees with persistable URI permissions). The storage permissions are also not required for accessing the application's external or internal storage directory that will contain the save files.
pack local_slot and constant in hir::Value
Instead of loading membase at the start of every function, just load it in HostToGuestThunk
vzeroupper in GuestToHostThunk before calling host function, and in HostToGuestThunk after calling function to prevent AVX dirty state slowdowns. In the future, check if CPU implements AVX as 128x2 and skip if so (https://john-h-k.github.io/VexTransitionPenalties.html)
Remove useless save/restore of ctx pointer, nothing modifies it and it prevents cpus from doing cross-function memory renaming (https://www.agner.org/forum/viewtopic.php?t=41). Could not remove the space on stack because of alignment issues, instead turned it into GUEST_SCRATCH64 which is a temporary that sequences may use
Reorder OpcodeInfo so that name is at offset 0, remove name and add GetOpcodeName function (name is only used for debug code, we are seperating frequently accessed data and rarely accessed data)
Add VECTOR_DENORMFLUSH opcode for handling output to DOT_PRODUCT and other opcodes that implicitly force denormal inputs/outputs to zero, will eventually use for implementing NJM
Rewrite sequences for LOAD_VECTOR_SHL/SHR. The mask with 0xf in it was pointless as all InstrEmit_ functions that create the load shift instructions do that in HIR. The tables are only used for nonzero constant inputs now, which are probably pretty rare. Instead of doing a shift and lookup, a base value is used for both in the constant table and adding/subtracting of the input is done
Reuse result of LoadVectorShl/Shr in InstrEmit_stvlx_, InstrEmit_stvrx_. We were previously calculating it twice which was contributing to the final sequences' fatness. Use OPCODE_SELECT instead of the sequence of or, andnot, and that it was using for merging
Add the proper unconditional denormal input flushing behavior to vfmadd, add it also to vfmsub (making the assumption it has the same behavior)
Remove constant propagation for DOT_PRODUCT_3/4
DOT_PRODUCT_3/4 now returns a vector with all four elements set to the result. (what we were doing before, truncating to float32 and then splatting didnt make any sense)
Add much more correct versions of DOT_PRODUCT_3/4, matching the Xb360's to 1 bit. Still needs work to be a perfect emulation.
Add constant folding for OPCODE_SELECT, OPCODE_INSERT, OPCODE_PERMUTE, OPCODE_SWIZZLE
Remove constant folding for DOT_PRODUCT
Removed the multibyte nop code I committed earlier, it doesnt help us much because nops are only used for debug stuff and its ugly and wouldnt survive in a pr to main
Check for AVX512BMI, use vpermb to shuffle if supported
Radosław Gliński