[llvm] c8c2218 - [TableGen][DecoderEmitter] Synthesize decoder table name in emitTable (#154255)
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llvm-commits at lists.llvm.org
Mon Aug 18 20:19:57 PDT 2025
Author: Sergei Barannikov
Date: 2025-08-19T06:19:54+03:00
New Revision: c8c2218c001e488dffee7ac840762c0cefaac742
URL: https://github.com/llvm/llvm-project/commit/c8c2218c001e488dffee7ac840762c0cefaac742
DIFF: https://github.com/llvm/llvm-project/commit/c8c2218c001e488dffee7ac840762c0cefaac742.diff
LOG: [TableGen][DecoderEmitter] Synthesize decoder table name in emitTable (#154255)
Previously, HW mode name was appended to decoder namespace name when
enumerating encodings, and then emitTable appended the bit width to it
to form the final table name. Let's do this all in one place.
A nice side effect is that this allows us to avoid having to deal with
std::string.
The changes in the tests are caused by the different order of tables.
Added:
Modified:
llvm/test/TableGen/HwModeEncodeDecode2.td
llvm/test/TableGen/HwModeEncodeDecode3.td
llvm/utils/TableGen/DecoderEmitter.cpp
Removed:
################################################################################
diff --git a/llvm/test/TableGen/HwModeEncodeDecode2.td b/llvm/test/TableGen/HwModeEncodeDecode2.td
index cf96dda6c8bf3..dc8773699a466 100644
--- a/llvm/test/TableGen/HwModeEncodeDecode2.td
+++ b/llvm/test/TableGen/HwModeEncodeDecode2.td
@@ -93,10 +93,6 @@ let OutOperandList = (outs) in {
}
}
-// DECODER-LABEL: DecoderTableAlt_ModeA32[] =
-// DECODER-DAG: Opcode: unrelated
-// DECODER-LABEL: DecoderTableAlt_ModeB32[] =
-// DECODER-DAG: Opcode: unrelated
// DECODER-LABEL: DecoderTable_ModeA32[] =
// DECODER-DAG: Opcode: fooTypeEncA:foo
// DECODER-DAG: Opcode: bar
@@ -104,11 +100,13 @@ let OutOperandList = (outs) in {
// DECODER-DAG: Opcode: fooTypeEncB:foo
// DECODER-DAG: Opcode: fooTypeEncA:baz
// DECODER-DAG: Opcode: bar
+// DECODER-LABEL: DecoderTableAlt_ModeA32[] =
+// DECODER-DAG: Opcode: unrelated
+// DECODER-LABEL: DecoderTableAlt_ModeB32[] =
+// DECODER-DAG: Opcode: unrelated
// DECODER-SUPPRESS-LABEL: DecoderTable32[] =
// DECODER-SUPPRESS-DAG: Opcode: bar
-// DECODER-SUPPRESS-LABEL: DecoderTableAlt32[] =
-// DECODER-SUPPRESS-DAG: Opcode: unrelated
// DECODER-SUPPRESS-LABEL: DecoderTable_ModeA32[] =
// DECODER-SUPPRESS-DAG: Opcode: fooTypeEncA:foo
// DECODER-SUPPRESS-NOT: Opcode: bar
@@ -116,3 +114,5 @@ let OutOperandList = (outs) in {
// DECODER-SUPPRESS-DAG: Opcode: fooTypeEncB:foo
// DECODER-SUPPRESS-DAG: Opcode: fooTypeEncA:baz
// DECODER-SUPPRESS-NOT: Opcode: bar
+// DECODER-SUPPRESS-LABEL: DecoderTableAlt32[] =
+// DECODER-SUPPRESS-DAG: Opcode: unrelated
diff --git a/llvm/test/TableGen/HwModeEncodeDecode3.td b/llvm/test/TableGen/HwModeEncodeDecode3.td
index c4d488d9d5f8f..2629af26be7c0 100644
--- a/llvm/test/TableGen/HwModeEncodeDecode3.td
+++ b/llvm/test/TableGen/HwModeEncodeDecode3.td
@@ -120,14 +120,6 @@ def unrelated: Instruction {
// DECODER-DAG: Opcode: bar
// DECODER-LABEL: DecoderTable64[] =
// DECODER-DAG: Opcode: fooTypeEncDefault:foo
-// DECODER-LABEL: DecoderTableAlt32[] =
-// DECODER-DAG: Opcode: unrelated
-// DECODER-LABEL: DecoderTableAlt_ModeA32[] =
-// DECODER-DAG: Opcode: unrelated
-// DECODER-LABEL: DecoderTableAlt_ModeB32[] =
-// DECODER-DAG: Opcode: unrelated
-// DECODER-LABEL: DecoderTableAlt_ModeC32[] =
-// DECODER-DAG: Opcode: unrelated
// DECODER-LABEL: DecoderTable_ModeA32[] =
// DECODER-DAG: Opcode: fooTypeEncA:foo
// DECODER-DAG: Opcode: bar
@@ -138,6 +130,14 @@ def unrelated: Instruction {
// DECODER-LABEL: DecoderTable_ModeC32[] =
// DECODER-DAG: Opcode: fooTypeEncC:foo
// DECODER-DAG: Opcode: bar
+// DECODER-LABEL: DecoderTableAlt32[] =
+// DECODER-DAG: Opcode: unrelated
+// DECODER-LABEL: DecoderTableAlt_ModeA32[] =
+// DECODER-DAG: Opcode: unrelated
+// DECODER-LABEL: DecoderTableAlt_ModeB32[] =
+// DECODER-DAG: Opcode: unrelated
+// DECODER-LABEL: DecoderTableAlt_ModeC32[] =
+// DECODER-DAG: Opcode: unrelated
// Under the 'O1' optimization level, unnecessary duplicate tables will be eliminated,
// reducing the four ‘Alt’ tables down to just one.
@@ -145,8 +145,6 @@ def unrelated: Instruction {
// DECODER-SUPPRESS-O1-DAG: Opcode: bar
// DECODER-SUPPRESS-O1-LABEL: DecoderTable64[] =
// DECODER-SUPPRESS-O1-DAG: Opcode: fooTypeEncDefault:foo
-// DECODER-SUPPRESS-O1-LABEL: DecoderTableAlt32[] =
-// DECODER-SUPPRESS-O1-DAG: Opcode: unrelated
// DECODER-SUPPRESS-O1-LABEL: DecoderTable_ModeA32[] =
// DECODER-SUPPRESS-O1-DAG: Opcode: fooTypeEncA:foo
// DECODER-SUPPRESS-O1-DAG: Opcode: bar
@@ -157,6 +155,8 @@ def unrelated: Instruction {
// DECODER-SUPPRESS-O1-LABEL: DecoderTable_ModeC32[] =
// DECODER-SUPPRESS-O1-DAG: Opcode: fooTypeEncC:foo
// DECODER-SUPPRESS-O1-DAG: Opcode: bar
+// DECODER-SUPPRESS-O1-LABEL: DecoderTableAlt32[] =
+// DECODER-SUPPRESS-O1-DAG: Opcode: unrelated
// Under the 'O2' optimization condition, instructions possessing the 'EncodingByHwMode'
// attribute will be extracted from their original DecoderNamespace and placed into their
@@ -169,8 +169,6 @@ def unrelated: Instruction {
// DECODER-SUPPRESS-O2-LABEL: DecoderTable64[] =
// DECODER-SUPPRESS-O2-NOT: Opcode: bar
// DECODER-SUPPRESS-O2-DAG: Opcode: fooTypeEncDefault:foo
-// DECODER-SUPPRESS-O2-LABEL: DecoderTableAlt32[] =
-// DECODER-SUPPRESS-O2-DAG: Opcode: unrelated
// DECODER-SUPPRESS-O2-LABEL: DecoderTable_ModeA32[] =
// DECODER-SUPPRESS-O2-DAG: Opcode: fooTypeEncA:foo
// DECODER-SUPPRESS-O2-NOT: Opcode: bar
@@ -181,6 +179,8 @@ def unrelated: Instruction {
// DECODER-SUPPRESS-O2-LABEL: DecoderTable_ModeC32[] =
// DECODER-SUPPRESS-O2-DAG: Opcode: fooTypeEncC:foo
// DECODER-SUPPRESS-O2-NOT: Opcode: bar
+// DECODER-SUPPRESS-O2-LABEL: DecoderTableAlt32[] =
+// DECODER-SUPPRESS-O2-DAG: Opcode: unrelated
// For 'bar' and 'unrelated', we didn't assign any HwModes for them,
// they should keep the same in the following four tables.
diff --git a/llvm/utils/TableGen/DecoderEmitter.cpp b/llvm/utils/TableGen/DecoderEmitter.cpp
index c1afbbdbcf459..c16d5b5d317d6 100644
--- a/llvm/utils/TableGen/DecoderEmitter.cpp
+++ b/llvm/utils/TableGen/DecoderEmitter.cpp
@@ -230,7 +230,7 @@ class DecoderEmitter {
// Emit the decoder state machine table. Returns a mask of MCD decoder ops
// that were emitted.
unsigned emitTable(formatted_raw_ostream &OS, DecoderTable &Table,
- unsigned BitWidth, StringRef Namespace,
+ StringRef Namespace, unsigned HwModeID, unsigned BitWidth,
ArrayRef<unsigned> EncodingIDs) const;
void emitInstrLenTable(formatted_raw_ostream &OS,
ArrayRef<unsigned> InstrLen) const;
@@ -805,8 +805,8 @@ unsigned Filter::usefulness() const {
// Emit the decoder state machine table. Returns a mask of MCD decoder ops
// that were emitted.
unsigned DecoderEmitter::emitTable(formatted_raw_ostream &OS,
- DecoderTable &Table, unsigned BitWidth,
- StringRef Namespace,
+ DecoderTable &Table, StringRef Namespace,
+ unsigned HwModeID, unsigned BitWidth,
ArrayRef<unsigned> EncodingIDs) const {
// We'll need to be able to map from a decoded opcode into the corresponding
// EncodingID for this specific combination of BitWidth and Namespace. This
@@ -818,8 +818,10 @@ unsigned DecoderEmitter::emitTable(formatted_raw_ostream &OS,
OpcodeToEncodingID[Target.getInstrIntValue(InstDef)] = EncodingID;
}
- OS << "static const uint8_t DecoderTable" << Namespace << BitWidth
- << "[] = {\n";
+ OS << "static const uint8_t DecoderTable" << Namespace;
+ if (HwModeID != DefaultMode)
+ OS << '_' << Target.getHwModes().getModeName(HwModeID);
+ OS << BitWidth << "[] = {\n";
// Emit ULEB128 encoded value to OS, returning the number of bytes emitted.
auto emitULEB128 = [](DecoderTable::const_iterator &I,
@@ -2501,8 +2503,9 @@ namespace {
NumberedAlias,
&Target.getInstruction(NumberedAlias->getValueAsDef("AliasOf")));
- // Map of (namespace, size) tuple to encoding IDs.
- std::map<std::pair<std::string, unsigned>, std::vector<unsigned>> EncMap;
+ // Map of (namespace, hwmode, size) tuple to encoding IDs.
+ std::map<std::tuple<StringRef, unsigned, unsigned>, std::vector<unsigned>>
+ EncMap;
std::map<unsigned, std::vector<OperandInfo>> Operands;
std::vector<unsigned> InstrLen;
bool IsVarLenInst = Target.hasVariableLengthEncodings();
@@ -2537,14 +2540,10 @@ namespace {
MaxInstLen = std::max(MaxInstLen, Len);
InstrLen[NEI] = Len;
}
- std::string DecoderNamespace =
- EncodingDef->getValueAsString("DecoderNamespace").str();
- // DecoderTables with DefaultMode should not have any suffix.
- if (NumberedEncoding.HwModeID != DefaultMode) {
- StringRef HwModeName = HWM.getModeName(NumberedEncoding.HwModeID);
- DecoderNamespace += ("_" + HwModeName).str();
- }
- EncMap[{DecoderNamespace, Size}].push_back(NEI);
+ StringRef DecoderNamespace =
+ EncodingDef->getValueAsString("DecoderNamespace");
+ EncMap[{DecoderNamespace, NumberedEncoding.HwModeID, Size}].push_back(
+ NEI);
} else {
NumEncodingsOmitted++;
}
@@ -2552,12 +2551,11 @@ namespace {
DecoderTableInfo TableInfo;
unsigned OpcodeMask = 0;
- for (const auto &[NSAndByteSize, EncodingIDs] : EncMap) {
- const std::string &DecoderNamespace = NSAndByteSize.first;
- const unsigned BitWidth = 8 * NSAndByteSize.second;
- // Emit the decoder for this namespace+width combination.
- FilterChooser FC(NumberedEncodings, EncodingIDs, Operands,
- IsVarLenInst ? MaxInstLen : BitWidth, this);
+ for (const auto &[Key, EncodingIDs] : EncMap) {
+ auto [DecoderNamespace, HwModeID, Size] = Key;
+ const unsigned BitWidth = IsVarLenInst ? MaxInstLen : 8 * Size;
+ // Emit the decoder for this (namespace, hwmode, width) combination.
+ FilterChooser FC(NumberedEncodings, EncodingIDs, Operands, BitWidth, this);
// The decode table is cleared for each top level decoder function. The
// predicates and decoders themselves, however, are shared across all
@@ -2573,8 +2571,8 @@ namespace {
TableInfo.Table.push_back(MCD::OPC_Fail);
// Print the table to the output stream.
- OpcodeMask |= emitTable(OS, TableInfo.Table, FC.getBitWidth(),
- DecoderNamespace, EncodingIDs);
+ OpcodeMask |= emitTable(OS, TableInfo.Table, DecoderNamespace, HwModeID,
+ BitWidth, EncodingIDs);
}
// For variable instruction, we emit a instruction length table
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