Files
llvm-project/llvm/test/TableGen/HwModeEncodeAPInt.td
Rahul Joshi 85f5953fca [LLVM][MC] Unique per-hw mode field encoding code in CodeEmitterGen (#172764)
Change CodeEmitterGen to de-duplicate case statements emitted for
encoding instruction fields for different HW modes when they contain the
same code. When 2 or more HW modes share the same code for encoding the
fields of an instruction, we currently generate a case statement for
each mode and emit the same code in each case body. Instead, unique the
case statement bodies and emit each body just once.

Some minor refactor to help with this:
1. Make `emitCaseMap` a standalone static function and use
`ListSeparator` to emit the case statements.
2. Add a type-alias for the map of cases.

No upstream target seems to use this feature (`EncodingInfos`) but this
results in ~3% code size reduction in a downstream target.
2025-12-18 09:31:59 -08:00

237 lines
7.7 KiB
TableGen

// This testcase is to test the correctness of HwMode encoding under the 'APInt' Mode.
// RUN: llvm-tblgen -gen-emitter -I %p/../../include %s | \
// RUN: FileCheck %s --check-prefix=ENCODER
include "llvm/Target/Target.td"
def archInstrInfo : InstrInfo { }
def arch : Target {
let InstructionSet = archInstrInfo;
}
def Myi32 : Operand<i32> {
let DecoderMethod = "DecodeMyi32";
}
def HasA : Predicate<"Subtarget->hasA()">;
def HasB : Predicate<"Subtarget->hasB()">;
def ModeA : HwMode<[HasA]>; // Mode 1
def ModeB : HwMode<[HasB]>; // Mode 2
def ModeC : HwMode<[]>; // Mode 3
def fooTypeEncDefault : InstructionEncoding {
let Size = 16;
field bits<128> SoftFail = 0;
bits<128> Inst;
bits<8> factor;
let Inst{127...120} = factor;
let Inst{3...2} = 0b10;
let Inst{1...0} = 0b00;
}
def fooTypeEncA : InstructionEncoding {
let Size = 16;
field bits<128> SoftFail = 0;
bits<128> Inst;
bits<8> factor;
let Inst{119...112} = factor;
let Inst{3...2} = 0b11;
let Inst{1...0} = 0b00;
}
def fooTypeEncB : InstructionEncoding {
let Size = 16;
field bits<128> SoftFail = 0;
bits<128> Inst;
bits<8> factor;
let Inst{119...112} = factor;
let Inst{111...110} = 0b11;
}
def fooTypeEncC : InstructionEncoding {
let Size = 16;
field bits<128> SoftFail = 0;
bits<128> Inst;
bits<8> factor;
let Inst{31...24} = factor;
let Inst{23...21} = 0b110;
let Inst{1...0} = 0b11;
}
// Test for DefaultMode as a selector.
def foo : Instruction {
bits<128> Inst;
let OutOperandList = (outs);
let InOperandList = (ins i32imm:$factor);
let EncodingInfos = EncodingByHwMode<
[ModeC, ModeA, ModeB, DefaultMode],
[fooTypeEncC, fooTypeEncA, fooTypeEncB, fooTypeEncDefault]>;
let AsmString = "foo $factor";
}
def bar: Instruction {
let OutOperandList = (outs);
let InOperandList = (ins i32imm:$factor);
let Size = 4;
bits<32> Inst;
bits<32> SoftFail;
bits<8> factor;
let Inst{31...24} = factor;
let Inst{1...0} = 0b10;
let AsmString = "bar $factor";
}
def baz : Instruction {
let OutOperandList = (outs);
let InOperandList = (ins i32imm:$factor);
bits<32> Inst;
let EncodingInfos = EncodingByHwMode<
[ModeB], [fooTypeEncA]
>;
let AsmString = "foo $factor";
}
def unrelated: Instruction {
let OutOperandList = (outs);
let DecoderNamespace = "Alt";
let InOperandList = (ins i32imm:$factor);
let Size = 4;
bits<32> Inst;
bits<32> SoftFail;
bits<8> factor;
let Inst{31...24} = factor;
let Inst{1...0} = 0b10;
let AsmString = "unrelated $factor";
}
// For 'bar' and 'unrelated', we didn't assign any HwModes for them,
// they should keep the same in the following four tables.
// For 'foo' we assigned four HwModes( includes 'DefaultMode' ),
// it's encodings should be different in the following four tables.
// For 'baz' we only assigned ModeB for it, so it will be presented
// as '0' in the tables of ModeA, ModeC and Default Mode.
// ENCODER-LABEL: static const uint64_t InstBits[] = {
// ENCODER-NEXT: UINT64_C(2), UINT64_C(0), // bar
// ENCODER-NEXT: UINT64_C(0), UINT64_C(0), // baz
// ENCODER-NEXT: UINT64_C(8), UINT64_C(0), // foo
// ENCODER-NEXT: UINT64_C(2), UINT64_C(0), // unrelated
// ENCODER-NEXT: };
// ENCODER-LABEL: static const uint64_t InstBits_ModeA[] = {
// ENCODER-NEXT: UINT64_C(2), UINT64_C(0), // bar
// ENCODER-NEXT: UINT64_C(0), UINT64_C(0), // baz
// ENCODER-NEXT: UINT64_C(12), UINT64_C(0), // foo
// ENCODER-NEXT: UINT64_C(2), UINT64_C(0), // unrelated
// ENCODER-NEXT: };
// ENCODER-LABEL: static const uint64_t InstBits_ModeB[] = {
// ENCODER-NEXT: UINT64_C(2), UINT64_C(0), // bar
// ENCODER-NEXT: UINT64_C(12), UINT64_C(0), // baz
// ENCODER-NEXT: UINT64_C(0), UINT64_C(211106232532992), // foo
// ENCODER-NEXT: UINT64_C(2), UINT64_C(0), // unrelated
// ENCODER-NEXT: };
// ENCODER-LABEL: static const uint64_t InstBits_ModeC[] = {
// ENCODER-NEXT: UINT64_C(2), UINT64_C(0), // bar
// ENCODER-NEXT: UINT64_C(0), UINT64_C(0), // baz
// ENCODER-NEXT: UINT64_C(12582915), UINT64_C(0), // foo
// ENCODER-NEXT: UINT64_C(2), UINT64_C(0), // unrelated
// ENCODER-NEXT: };
// ENCODER: const uint64_t *InstBitsByHw;
// ENCODER: constexpr unsigned FirstSupportedOpcode
// ENCODER: const unsigned opcode = MI.getOpcode();
// ENCODER: if (opcode < FirstSupportedOpcode)
// ENCODER: unsigned TableIndex = opcode - FirstSupportedOpcode
// ENCODER: if (Scratch.getBitWidth() != 128)
// ENCODER: Scratch = Scratch.zext(128);
// ENCODER: Inst = APInt(128, ArrayRef(InstBits + TableIndex * 2, 2));
// ENCODER: APInt &Value = Inst;
// ENCODER: APInt &op = Scratch;
// ENCODER: switch (opcode) {
// ENCODER-LABEL: case ::bar:
// ENCODER-LABEL: case ::unrelated:
// ENCODER-NOT: getHwMode
// ENCODER-LABEL: case ::foo: {
// ENCODER: unsigned HwMode = STI.getHwMode(MCSubtargetInfo::HwMode_EncodingInfo);
// ENCODER: switch (HwMode) {
// ENCODER: default: llvm_unreachable("Unknown hardware mode!"); break;
// ENCODER: case 0: InstBitsByHw = InstBits; break;
// ENCODER: case 1: InstBitsByHw = InstBits_ModeA; break;
// ENCODER: case 2: InstBitsByHw = InstBits_ModeB; break;
// ENCODER: case 3: InstBitsByHw = InstBits_ModeC; break;
// ENCODER: };
// ENCODER: Inst = APInt(128, ArrayRef(InstBitsByHw + TableIndex * 2, 2));
// ENCODER: Value = Inst;
// ENCODER: switch (HwMode) {
// ENCODER: default: llvm_unreachable("Unhandled HwMode");
// ENCODER: case 1:
// ENCODER: case 2: {
// ENCODER: op.clearAllBits();
// ENCODER: getMachineOpValue(MI, MI.getOperand(0), op, Fixups, STI);
// ENCODER: Value.insertBits(op.extractBitsAsZExtValue(8, 0), 112, 8);
// ENCODER: break;
// ENCODER: }
// ENCODER: case 0: {
// ENCODER: op.clearAllBits();
// ENCODER: getMachineOpValue(MI, MI.getOperand(0), op, Fixups, STI);
// ENCODER: Value.insertBits(op.extractBitsAsZExtValue(8, 0), 120, 8);
// ENCODER: break;
// ENCODER: }
// ENCODER: case 3: {
// ENCODER: op.clearAllBits();
// ENCODER: getMachineOpValue(MI, MI.getOperand(0), op, Fixups, STI);
// ENCODER: Value.insertBits(op.extractBitsAsZExtValue(8, 0), 24, 8);
// ENCODER: break;
// ENCODER: }
// ENCODER-LABEL: case ::baz: {
// ENCODER: unsigned HwMode = STI.getHwMode(MCSubtargetInfo::HwMode_EncodingInfo);
// ENCODER: switch (HwMode) {
// ENCODER: default: llvm_unreachable("Unknown hardware mode!"); break;
// ENCODER: case 2: InstBitsByHw = InstBits_ModeB; break;
// ENCODER: };
// ENCODER: Inst = APInt(128, ArrayRef(InstBitsByHw + TableIndex * 2, 2));
// ENCODER: Value = Inst;
// ENCODER: switch (HwMode) {
// ENCODER: default: llvm_unreachable("Unhandled HwMode");
// ENCODER: case 2: {
// ENCODER: getMachineOpValue(MI, MI.getOperand(0), op, Fixups, STI);
// ENCODER: Value.insertBits(op.extractBitsAsZExtValue(8, 0), 112, 8);
// ENCODER: break;
// ENCODER: }
// ENCODER-LABEL: uint32_t archMCCodeEmitter::getOperandBitOffset
// ENCODER: switch (MI.getOpcode()) {
// ENCODER-LABEL: case ::bar:
// ENCODER-LABEL: case ::unrelated: {
// ENCODER-NOT: getHwMode
// ENCODER-LABEL: case ::foo: {
// ENCODER: unsigned HwMode = STI.getHwMode(MCSubtargetInfo::HwMode_EncodingInfo);
// ENCODER: switch (HwMode) {
// ENCODER: default: llvm_unreachable("Unhandled HwMode");
// ENCODER: case 1:
// ENCODER: case 2: {
// ENCODER: switch (OpNum) {
// ENCODER: case 0:
// ENCODER: return 112;
// ENCODER: }
// ENCODER: break;
// ENCODER: }
// ENCODER: case 0: {
// ENCODER: switch (OpNum) {
// ENCODER: case 0:
// ENCODER: return 120;
// ENCODER: }
// ENCODER: break;
// ENCODER: }
// ENCODER: case 3: {
// ENCODER: switch (OpNum) {
// ENCODER: case 0:
// ENCODER: return 24;
// ENCODER: }
// ENCODER: break;
// ENCODER: }
// ENCODER: }
// ENCODER: break;
// ENCODER: }