9375962ac9
The vast majority of the following (very common) opcodes were always called with identical arguments: - `GIM_CheckType` for the root - `GIM_CheckRegBankForClass` for the root - `GIR_Copy` between the old and new root - `GIR_ConstrainSelectedInstOperands` on the new root - `GIR_BuildMI` to create the new root I added overloaded version of each opcode specialized for the root instructions. It always saves between 1 and 2 bytes per instance depending on the number of arguments specialized into the opcode. Some of these opcodes had between 5 and 15k occurences in the AArch64 GlobalISel Match Table. Additionally, the following opcodes are almost always used in the same sequence: - `GIR_EraseFromParent 0` + `GIR_Done` - `GIR_EraseRootFromParent_Done` has been created to do both. Saves 2 bytes per occurence. - `GIR_IsSafeToFold` was *always* called for each InsnID except 0. - Changed the opcode to take the number of instructions to check after `MI[0]` The savings from these are pretty neat. For `AArch64GenGlobalISel.inc`: - `AArch64InstructionSelector.cpp.o` goes down from 772kb to 704kb (-10% code size) - Self-reported MatchTable size goes from 420380 bytes to 352426 bytes (~ -17%) A smaller match table means a faster match table because we spend less time iterating and decoding. I don't have a solid measurement methodology for GlobalISel performance so I don't have precise numbers but I saw a few % of improvements in a simple testcase.
73 lines
4.7 KiB
TableGen
73 lines
4.7 KiB
TableGen
// RUN: llvm-tblgen -gen-global-isel -I %p/../../include -I %p/Common -optimize-match-table=false %s -o %T/context-non-optimized.cpp
|
|
// RUN: FileCheck %s --check-prefixes=CHECK_NOPT -input-file=%T/context-non-optimized.cpp
|
|
// RUN: llvm-tblgen -gen-global-isel -I %p/../../include -I %p/Common -optimize-match-table=true %s -o %T/context-optimized.cpp
|
|
// RUN: FileCheck %s --check-prefixes=CHECK_OPT -input-file=%T/context-optimized.cpp
|
|
|
|
|
|
|
|
include "llvm/Target/Target.td"
|
|
include "GlobalISelEmitterCommon.td"
|
|
|
|
def test_atomic_op_frag : PatFrag<(ops node:$ptr, node:$val),
|
|
(atomic_swap node:$ptr, node:$val)> {
|
|
let GISelPredicateCode = [{ return !MRI.use_nodbg_empty(MI.getOperand(0).getReg()); }];
|
|
let IsAtomic = 1;
|
|
let MemoryVT = i32;
|
|
}
|
|
|
|
def INSN : I<(outs GPR32:$dst), (ins GPR32Op:$src1, GPR32Op:$src2), []>;
|
|
|
|
def : Pat<(test_atomic_op_frag GPR32:$ptr, GPR32:$val) ,
|
|
(INSN GPR32:$ptr, GPR32:$val)>;
|
|
|
|
// CHECK_NOPT-LABEL: const uint8_t *MyTargetInstructionSelector::getMatchTable() const {
|
|
// CHECK_NOPT-NEXT: constexpr static uint8_t MatchTable0[] = {
|
|
// CHECK_NOPT-NEXT: GIM_Try, /*On fail goto*//*Label 0*/ GIMT_Encode4(52), // Rule ID 0 //
|
|
// CHECK_NOPT-NEXT: GIM_CheckNumOperands, /*MI*/0, /*Expected*/3,
|
|
// CHECK_NOPT-NEXT: GIM_CheckOpcode, /*MI*/0, GIMT_Encode2(TargetOpcode::G_ATOMICRMW_XCHG),
|
|
// CHECK_NOPT-NEXT: GIM_CheckMemorySizeEqualTo, /*MI*/0, /*MMO*/0, /*Size*/GIMT_Encode4(4),
|
|
// CHECK_NOPT-NEXT: // MIs[0] DstI[dst]
|
|
// CHECK_NOPT-NEXT: GIM_RootCheckType, /*Op*/0, /*Type*/GILLT_s32,
|
|
// CHECK_NOPT-NEXT: GIM_RootCheckRegBankForClass, /*Op*/0, /*RC*/GIMT_Encode2(MyTarget::GPR32RegClassID),
|
|
// CHECK_NOPT-NEXT: // MIs[0] ptr
|
|
// CHECK_NOPT-NEXT: GIM_CheckPointerToAny, /*MI*/0, /*Op*/1, /*SizeInBits*/32,
|
|
// CHECK_NOPT-NEXT: GIM_RootCheckRegBankForClass, /*Op*/1, /*RC*/GIMT_Encode2(MyTarget::GPR32RegClassID),
|
|
// CHECK_NOPT-NEXT: // MIs[0] val
|
|
// CHECK_NOPT-NEXT: GIM_RootCheckType, /*Op*/2, /*Type*/GILLT_s32,
|
|
// CHECK_NOPT-NEXT: GIM_RootCheckRegBankForClass, /*Op*/2, /*RC*/GIMT_Encode2(MyTarget::GPR32RegClassID),
|
|
// CHECK_NOPT-NEXT: GIM_CheckCxxInsnPredicate, /*MI*/0, /*FnId*/GIMT_Encode2(GICXXPred_MI_Predicate_test_atomic_op_frag),
|
|
// CHECK_NOPT-NEXT: // (atomic_swap:{ *:[i32] } GPR32:{ *:[i32] }:$ptr, GPR32:{ *:[i32] }:$val)<<P:Predicate_test_atomic_op_frag>> => (INSN:{ *:[i32] } GPR32:{ *:[i32] }:$ptr, GPR32:{ *:[i32] }:$val)
|
|
// CHECK_NOPT-NEXT: GIR_MutateOpcode, /*InsnID*/0, /*RecycleInsnID*/0, /*Opcode*/GIMT_Encode2(MyTarget::INSN),
|
|
// CHECK_NOPT-NEXT: GIR_RootConstrainSelectedInstOperands,
|
|
// CHECK_NOPT-NEXT: // GIR_Coverage, 0,
|
|
// CHECK_NOPT-NEXT: GIR_Done,
|
|
// CHECK_NOPT-NEXT: // Label 0: @52
|
|
// CHECK_NOPT-NEXT: GIM_Reject,
|
|
// CHECK_NOPT-NEXT: };
|
|
// CHECK_NOPT-NEXT: return MatchTable0;
|
|
// CHECK_NOPT-NEXT: }
|
|
|
|
// CHECK_OPT-LABEL: const uint8_t *MyTargetInstructionSelector::getMatchTable() const {
|
|
// CHECK_OPT-NEXT: constexpr static uint8_t MatchTable0[] = {
|
|
// CHECK_OPT-NEXT: GIM_Try, /*On fail goto*//*Label 0*/ GIMT_Encode4(49), // Rule ID 0 //
|
|
// CHECK_OPT-NEXT: GIM_CheckOpcode, /*MI*/0, GIMT_Encode2(TargetOpcode::G_ATOMICRMW_XCHG),
|
|
// CHECK_OPT-NEXT: GIM_RootCheckType, /*Op*/0, /*Type*/GILLT_s32,
|
|
// CHECK_OPT-NEXT: GIM_RootCheckType, /*Op*/2, /*Type*/GILLT_s32,
|
|
// CHECK_OPT-NEXT: GIM_CheckMemorySizeEqualTo, /*MI*/0, /*MMO*/0, /*Size*/GIMT_Encode4(4),
|
|
// CHECK_OPT-NEXT: GIM_RootCheckRegBankForClass, /*Op*/0, /*RC*/GIMT_Encode2(MyTarget::GPR32RegClassID),
|
|
// CHECK_OPT-NEXT: // MIs[0] ptr
|
|
// CHECK_OPT-NEXT: GIM_CheckPointerToAny, /*MI*/0, /*Op*/1, /*SizeInBits*/32,
|
|
// CHECK_OPT-NEXT: GIM_RootCheckRegBankForClass, /*Op*/1, /*RC*/GIMT_Encode2(MyTarget::GPR32RegClassID),
|
|
// CHECK_OPT-NEXT: GIM_RootCheckRegBankForClass, /*Op*/2, /*RC*/GIMT_Encode2(MyTarget::GPR32RegClassID),
|
|
// CHECK_OPT-NEXT: GIM_CheckCxxInsnPredicate, /*MI*/0, /*FnId*/GIMT_Encode2(GICXXPred_MI_Predicate_test_atomic_op_frag),
|
|
// CHECK_OPT-NEXT: // (atomic_swap:{ *:[i32] } GPR32:{ *:[i32] }:$ptr, GPR32:{ *:[i32] }:$val)<<P:Predicate_test_atomic_op_frag>> => (INSN:{ *:[i32] } GPR32:{ *:[i32] }:$ptr, GPR32:{ *:[i32] }:$val)
|
|
// CHECK_OPT-NEXT: GIR_MutateOpcode, /*InsnID*/0, /*RecycleInsnID*/0, /*Opcode*/GIMT_Encode2(MyTarget::INSN),
|
|
// CHECK_OPT-NEXT: GIR_RootConstrainSelectedInstOperands,
|
|
// CHECK_OPT-NEXT: // GIR_Coverage, 0,
|
|
// CHECK_OPT-NEXT: GIR_Done,
|
|
// CHECK_OPT-NEXT: // Label 0: @49
|
|
// CHECK_OPT-NEXT: GIM_Reject,
|
|
// CHECK_OPT-NEXT: };
|
|
// CHECK_OPT-NEXT: return MatchTable0;
|
|
// CHECK_OPT-NEXT: }
|