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-rw-r--r--mlir/lib/Transforms/Utils/DialectConversion.cpp455
1 files changed, 214 insertions, 241 deletions
diff --git a/mlir/lib/Transforms/Utils/DialectConversion.cpp b/mlir/lib/Transforms/Utils/DialectConversion.cpp
index 255b0ba..403321d 100644
--- a/mlir/lib/Transforms/Utils/DialectConversion.cpp
+++ b/mlir/lib/Transforms/Utils/DialectConversion.cpp
@@ -11,6 +11,7 @@
#include "mlir/IR/Block.h"
#include "mlir/IR/Builders.h"
#include "mlir/IR/BuiltinOps.h"
+#include "mlir/IR/Dominance.h"
#include "mlir/IR/IRMapping.h"
#include "mlir/IR/Iterators.h"
#include "mlir/Interfaces/FunctionInterfaces.h"
@@ -63,11 +64,55 @@ static OpBuilder::InsertPoint computeInsertPoint(Value value) {
return OpBuilder::InsertPoint(insertBlock, insertPt);
}
+/// Helper function that computes an insertion point where the given values are
+/// defined and can be used without a dominance violation.
+static OpBuilder::InsertPoint computeInsertPoint(ArrayRef<Value> vals) {
+ assert(!vals.empty() && "expected at least one value");
+ DominanceInfo domInfo;
+ OpBuilder::InsertPoint pt = computeInsertPoint(vals.front());
+ for (Value v : vals.drop_front()) {
+ // Choose the "later" insertion point.
+ OpBuilder::InsertPoint nextPt = computeInsertPoint(v);
+ if (domInfo.dominates(pt.getBlock(), pt.getPoint(), nextPt.getBlock(),
+ nextPt.getPoint())) {
+ // pt is before nextPt => choose nextPt.
+ pt = nextPt;
+ } else {
+#ifndef NDEBUG
+ // nextPt should be before pt => choose pt.
+ // If pt, nextPt are no dominance relationship, then there is no valid
+ // insertion point at which all given values are defined.
+ bool dom = domInfo.dominates(nextPt.getBlock(), nextPt.getPoint(),
+ pt.getBlock(), pt.getPoint());
+ assert(dom && "unable to find valid insertion point");
+#endif // NDEBUG
+ }
+ }
+ return pt;
+}
+
//===----------------------------------------------------------------------===//
// ConversionValueMapping
//===----------------------------------------------------------------------===//
+/// A vector of SSA values, optimized for the most common case of a single
+/// value.
+using ValueVector = SmallVector<Value, 1>;
+
namespace {
+
+/// Helper class to make it possible to use `ValueVector` as a key in DenseMap.
+struct ValueVectorMapInfo {
+ static ValueVector getEmptyKey() { return ValueVector{Value()}; }
+ static ValueVector getTombstoneKey() { return ValueVector{Value(), Value()}; }
+ static ::llvm::hash_code getHashValue(const ValueVector &val) {
+ return ::llvm::hash_combine_range(val.begin(), val.end());
+ }
+ static bool isEqual(const ValueVector &LHS, const ValueVector &RHS) {
+ return LHS == RHS;
+ }
+};
+
/// This class wraps a IRMapping to provide recursive lookup
/// functionality, i.e. we will traverse if the mapped value also has a mapping.
struct ConversionValueMapping {
@@ -75,68 +120,128 @@ struct ConversionValueMapping {
/// false positives.
bool isMappedTo(Value value) const { return mappedTo.contains(value); }
- /// Lookup the most recently mapped value with the desired type in the
+ /// Lookup the most recently mapped values with the desired types in the
/// mapping.
///
/// Special cases:
- /// - If the desired type is "null", simply return the most recently mapped
- /// value.
- /// - If there is no mapping to the desired type, also return the most
- /// recently mapped value.
- /// - If there is no mapping for the given value at all, return the given
+ /// - If the desired type range is empty, simply return the most recently
+ /// mapped values.
+ /// - If there is no mapping to the desired types, also return the most
+ /// recently mapped values.
+ /// - If there is no mapping for the given values at all, return the given
/// value.
- Value lookupOrDefault(Value from, Type desiredType = nullptr) const;
+ ValueVector lookupOrDefault(Value from, TypeRange desiredTypes = {}) const;
- /// Lookup a mapped value within the map, or return null if a mapping does not
- /// exist. If a mapping exists, this follows the same behavior of
- /// `lookupOrDefault`.
- Value lookupOrNull(Value from, Type desiredType = nullptr) const;
+ /// Lookup the given value within the map, or return an empty vector if the
+ /// value is not mapped. If it is mapped, this follows the same behavior
+ /// as `lookupOrDefault`.
+ ValueVector lookupOrNull(Value from, TypeRange desiredTypes = {}) const;
- /// Map a value to the one provided.
- void map(Value oldVal, Value newVal) {
+ template <typename T>
+ struct IsValueVector : std::is_same<std::decay_t<T>, ValueVector> {};
+
+ /// Map a value vector to the one provided.
+ template <typename OldVal, typename NewVal>
+ std::enable_if_t<IsValueVector<OldVal>::value && IsValueVector<NewVal>::value>
+ map(OldVal &&oldVal, NewVal &&newVal) {
LLVM_DEBUG({
- for (Value it = newVal; it; it = mapping.lookupOrNull(it))
- assert(it != oldVal && "inserting cyclic mapping");
+ ValueVector next(newVal);
+ while (true) {
+ assert(next != oldVal && "inserting cyclic mapping");
+ auto it = mapping.find(next);
+ if (it == mapping.end())
+ break;
+ next = it->second;
+ }
});
- mapping.map(oldVal, newVal);
- mappedTo.insert(newVal);
+ for (Value v : newVal)
+ mappedTo.insert(v);
+
+ mapping[std::forward<OldVal>(oldVal)] = std::forward<NewVal>(newVal);
}
- /// Drop the last mapping for the given value.
- void erase(Value value) { mapping.erase(value); }
+ /// Map a value vector or single value to the one provided.
+ template <typename OldVal, typename NewVal>
+ std::enable_if_t<!IsValueVector<OldVal>::value ||
+ !IsValueVector<NewVal>::value>
+ map(OldVal &&oldVal, NewVal &&newVal) {
+ if constexpr (IsValueVector<OldVal>{}) {
+ map(std::forward<OldVal>(oldVal), ValueVector{newVal});
+ } else if constexpr (IsValueVector<NewVal>{}) {
+ map(ValueVector{oldVal}, std::forward<NewVal>(newVal));
+ } else {
+ map(ValueVector{oldVal}, ValueVector{newVal});
+ }
+ }
+
+ /// Drop the last mapping for the given values.
+ void erase(const ValueVector &value) { mapping.erase(value); }
private:
/// Current value mappings.
- IRMapping mapping;
+ DenseMap<ValueVector, ValueVector, ValueVectorMapInfo> mapping;
/// All SSA values that are mapped to. May contain false positives.
DenseSet<Value> mappedTo;
};
} // namespace
-Value ConversionValueMapping::lookupOrDefault(Value from,
- Type desiredType) const {
- // Try to find the deepest value that has the desired type. If there is no
- // such value, simply return the deepest value.
- Value desiredValue;
+ValueVector
+ConversionValueMapping::lookupOrDefault(Value from,
+ TypeRange desiredTypes) const {
+ // Try to find the deepest values that have the desired types. If there is no
+ // such mapping, simply return the deepest values.
+ ValueVector desiredValue;
+ ValueVector current{from};
do {
- if (!desiredType || from.getType() == desiredType)
- desiredValue = from;
+ // Store the current value if the types match.
+ if (TypeRange(ValueRange(current)) == desiredTypes)
+ desiredValue = current;
+
+ // If possible, Replace each value with (one or multiple) mapped values.
+ ValueVector next;
+ for (Value v : current) {
+ auto it = mapping.find({v});
+ if (it != mapping.end()) {
+ llvm::append_range(next, it->second);
+ } else {
+ next.push_back(v);
+ }
+ }
+ if (next != current) {
+ // If at least one value was replaced, continue the lookup from there.
+ current = std::move(next);
+ continue;
+ }
- Value mappedValue = mapping.lookupOrNull(from);
- if (!mappedValue)
+ // Otherwise: Check if there is a mapping for the entire vector. Such
+ // mappings are materializations. (N:M mapping are not supported for value
+ // replacements.)
+ //
+ // Note: From a correctness point of view, materializations do not have to
+ // be stored (and looked up) in the mapping. But for performance reasons,
+ // we choose to reuse existing IR (when possible) instead of creating it
+ // multiple times.
+ auto it = mapping.find(current);
+ if (it == mapping.end()) {
+ // No mapping found: The lookup stops here.
break;
- from = mappedValue;
+ }
+ current = it->second;
} while (true);
- // If the desired value was found use it, otherwise default to the leaf value.
- return desiredValue ? desiredValue : from;
+ // If the desired values were found use them, otherwise default to the leaf
+ // values.
+ // Note: If `desiredTypes` is empty, this function always returns `current`.
+ return !desiredValue.empty() ? std::move(desiredValue) : std::move(current);
}
-Value ConversionValueMapping::lookupOrNull(Value from, Type desiredType) const {
- Value result = lookupOrDefault(from, desiredType);
- if (result == from || (desiredType && result.getType() != desiredType))
- return nullptr;
+ValueVector ConversionValueMapping::lookupOrNull(Value from,
+ TypeRange desiredTypes) const {
+ ValueVector result = lookupOrDefault(from, desiredTypes);
+ if (result == ValueVector{from} ||
+ (!desiredTypes.empty() && TypeRange(ValueRange(result)) != desiredTypes))
+ return {};
return result;
}
@@ -651,10 +756,6 @@ public:
/// The type of materialization.
enum MaterializationKind {
- /// This materialization materializes a conversion for an illegal block
- /// argument type, to the original one.
- Argument,
-
/// This materialization materializes a conversion from an illegal type to a
/// legal one.
Target,
@@ -673,7 +774,7 @@ public:
UnrealizedConversionCastOp op,
const TypeConverter *converter,
MaterializationKind kind, Type originalType,
- Value mappedValue);
+ ValueVector mappedValues);
static bool classof(const IRRewrite *rewrite) {
return rewrite->getKind() == Kind::UnresolvedMaterialization;
@@ -708,9 +809,9 @@ private:
/// materializations.
Type originalType;
- /// The value in the conversion value mapping that is being replaced by the
+ /// The values in the conversion value mapping that are being replaced by the
/// results of this unresolved materialization.
- Value mappedValue;
+ ValueVector mappedValues;
};
} // namespace
@@ -779,7 +880,7 @@ struct ConversionPatternRewriterImpl : public RewriterBase::Listener {
LogicalResult remapValues(StringRef valueDiagTag,
std::optional<Location> inputLoc,
PatternRewriter &rewriter, ValueRange values,
- SmallVector<SmallVector<Value>> &remapped);
+ SmallVector<ValueVector> &remapped);
/// Return "true" if the given operation is ignored, and does not need to be
/// converted.
@@ -820,39 +921,14 @@ struct ConversionPatternRewriterImpl : public RewriterBase::Listener {
/// If a cast op was built, it can optionally be returned with the `castOp`
/// output argument.
///
- /// If `valueToMap` is set to a non-null Value, then that value is mapped to
+ /// If `valuesToMap` is set to a non-null Value, then that value is mapped to
/// the results of the unresolved materialization in the conversion value
/// mapping.
ValueRange buildUnresolvedMaterialization(
MaterializationKind kind, OpBuilder::InsertPoint ip, Location loc,
- Value valueToMap, ValueRange inputs, TypeRange outputTypes,
+ ValueVector valuesToMap, ValueRange inputs, TypeRange outputTypes,
Type originalType, const TypeConverter *converter,
UnrealizedConversionCastOp *castOp = nullptr);
- Value buildUnresolvedMaterialization(
- MaterializationKind kind, OpBuilder::InsertPoint ip, Location loc,
- Value valueToMap, ValueRange inputs, Type outputType, Type originalType,
- const TypeConverter *converter,
- UnrealizedConversionCastOp *castOp = nullptr) {
- return buildUnresolvedMaterialization(kind, ip, loc, valueToMap, inputs,
- TypeRange(outputType), originalType,
- converter, castOp)
- .front();
- }
-
- /// Build an N:1 materialization for the given original value that was
- /// replaced with the given replacement values.
- ///
- /// This is a workaround around incomplete 1:N support in the dialect
- /// conversion driver. The conversion mapping can store only 1:1 replacements
- /// and the conversion patterns only support single Value replacements in the
- /// adaptor, so N values must be converted back to a single value. This
- /// function will be deleted when full 1:N support has been added.
- ///
- /// This function inserts an argument materialization back to the original
- /// type.
- void insertNTo1Materialization(OpBuilder::InsertPoint ip, Location loc,
- ValueRange replacements, Value originalValue,
- const TypeConverter *converter);
/// Find a replacement value for the given SSA value in the conversion value
/// mapping. The replacement value must have the same type as the given SSA
@@ -862,16 +938,6 @@ struct ConversionPatternRewriterImpl : public RewriterBase::Listener {
Value findOrBuildReplacementValue(Value value,
const TypeConverter *converter);
- /// Unpack an N:1 materialization and return the inputs of the
- /// materialization. This function unpacks only those materializations that
- /// were built with `insertNTo1Materialization`.
- ///
- /// This is a workaround around incomplete 1:N support in the dialect
- /// conversion driver. It allows us to write 1:N conversion patterns while
- /// 1:N support is still missing in the conversion value mapping. This
- /// function will be deleted when full 1:N support has been added.
- SmallVector<Value> unpackNTo1Materialization(Value value);
-
//===--------------------------------------------------------------------===//
// Rewriter Notification Hooks
//===--------------------------------------------------------------------===//
@@ -974,10 +1040,6 @@ struct ConversionPatternRewriterImpl : public RewriterBase::Listener {
DenseMap<UnrealizedConversionCastOp, UnresolvedMaterializationRewrite *>
unresolvedMaterializations;
- /// A set of all N:1 materializations that were added to work around
- /// incomplete 1:N support in the dialect conversion driver.
- DenseSet<UnrealizedConversionCastOp> nTo1TempMaterializations;
-
/// The current type converter, or nullptr if no type converter is currently
/// active.
const TypeConverter *currentTypeConverter = nullptr;
@@ -1041,7 +1103,7 @@ void ReplaceBlockArgRewrite::commit(RewriterBase &rewriter) {
});
}
-void ReplaceBlockArgRewrite::rollback() { rewriterImpl.mapping.erase(arg); }
+void ReplaceBlockArgRewrite::rollback() { rewriterImpl.mapping.erase({arg}); }
void ReplaceOperationRewrite::commit(RewriterBase &rewriter) {
auto *listener =
@@ -1082,7 +1144,7 @@ void ReplaceOperationRewrite::commit(RewriterBase &rewriter) {
void ReplaceOperationRewrite::rollback() {
for (auto result : op->getResults())
- rewriterImpl.mapping.erase(result);
+ rewriterImpl.mapping.erase({result});
}
void ReplaceOperationRewrite::cleanup(RewriterBase &rewriter) {
@@ -1101,20 +1163,19 @@ void CreateOperationRewrite::rollback() {
UnresolvedMaterializationRewrite::UnresolvedMaterializationRewrite(
ConversionPatternRewriterImpl &rewriterImpl, UnrealizedConversionCastOp op,
const TypeConverter *converter, MaterializationKind kind, Type originalType,
- Value mappedValue)
+ ValueVector mappedValues)
: OperationRewrite(Kind::UnresolvedMaterialization, rewriterImpl, op),
converterAndKind(converter, kind), originalType(originalType),
- mappedValue(mappedValue) {
+ mappedValues(std::move(mappedValues)) {
assert((!originalType || kind == MaterializationKind::Target) &&
"original type is valid only for target materializations");
rewriterImpl.unresolvedMaterializations[op] = this;
}
void UnresolvedMaterializationRewrite::rollback() {
- if (mappedValue)
- rewriterImpl.mapping.erase(mappedValue);
+ if (!mappedValues.empty())
+ rewriterImpl.mapping.erase(mappedValues);
rewriterImpl.unresolvedMaterializations.erase(getOperation());
- rewriterImpl.nTo1TempMaterializations.erase(getOperation());
op->erase();
}
@@ -1160,7 +1221,7 @@ void ConversionPatternRewriterImpl::undoRewrites(unsigned numRewritesToKeep) {
LogicalResult ConversionPatternRewriterImpl::remapValues(
StringRef valueDiagTag, std::optional<Location> inputLoc,
PatternRewriter &rewriter, ValueRange values,
- SmallVector<SmallVector<Value>> &remapped) {
+ SmallVector<ValueVector> &remapped) {
remapped.reserve(llvm::size(values));
for (const auto &it : llvm::enumerate(values)) {
@@ -1168,18 +1229,11 @@ LogicalResult ConversionPatternRewriterImpl::remapValues(
Type origType = operand.getType();
Location operandLoc = inputLoc ? *inputLoc : operand.getLoc();
- // Find the most recently mapped value. Unpack all temporary N:1
- // materializations. Such conversions are a workaround around missing
- // 1:N support in the ConversionValueMapping. (The conversion patterns
- // already support 1:N replacements.)
- Value repl = mapping.lookupOrDefault(operand);
- SmallVector<Value> unpacked = unpackNTo1Materialization(repl);
-
if (!currentTypeConverter) {
// The current pattern does not have a type converter. I.e., it does not
// distinguish between legal and illegal types. For each operand, simply
- // pass through the most recently mapped value.
- remapped.push_back(std::move(unpacked));
+ // pass through the most recently mapped values.
+ remapped.push_back(mapping.lookupOrDefault(operand));
continue;
}
@@ -1192,51 +1246,28 @@ LogicalResult ConversionPatternRewriterImpl::remapValues(
});
return failure();
}
-
// If a type is converted to 0 types, there is nothing to do.
if (legalTypes.empty()) {
remapped.push_back({});
continue;
}
- if (legalTypes.size() != 1) {
- // TODO: This is a 1:N conversion. The conversion value mapping does not
- // store such materializations yet. If the types of the most recently
- // mapped values do not match, build a target materialization.
- ValueRange unpackedRange(unpacked);
- if (TypeRange(unpackedRange) == legalTypes) {
- remapped.push_back(std::move(unpacked));
- continue;
- }
-
- // Insert a target materialization if the current pattern expects
- // different legalized types.
- ValueRange targetMat = buildUnresolvedMaterialization(
- MaterializationKind::Target, computeInsertPoint(repl), operandLoc,
- /*valueToMap=*/Value(), /*inputs=*/unpacked,
- /*outputType=*/legalTypes, /*originalType=*/origType,
- currentTypeConverter);
- remapped.push_back(targetMat);
+ ValueVector repl = mapping.lookupOrDefault(operand, legalTypes);
+ if (!repl.empty() && TypeRange(ValueRange(repl)) == legalTypes) {
+ // Mapped values have the correct type or there is an existing
+ // materialization. Or the operand is not mapped at all and has the
+ // correct type.
+ remapped.push_back(std::move(repl));
continue;
}
- // Handle 1->1 type conversions.
- Type desiredType = legalTypes.front();
- // Try to find a mapped value with the desired type. (Or the operand itself
- // if the value is not mapped at all.)
- Value newOperand = mapping.lookupOrDefault(operand, desiredType);
- if (newOperand.getType() != desiredType) {
- // If the looked up value's type does not have the desired type, it means
- // that the value was replaced with a value of different type and no
- // target materialization was created yet.
- Value castValue = buildUnresolvedMaterialization(
- MaterializationKind::Target, computeInsertPoint(newOperand),
- operandLoc, /*valueToMap=*/newOperand, /*inputs=*/unpacked,
- /*outputType=*/desiredType, /*originalType=*/origType,
- currentTypeConverter);
- newOperand = castValue;
- }
- remapped.push_back({newOperand});
+ // Create a materialization for the most recently mapped values.
+ repl = mapping.lookupOrDefault(operand);
+ ValueRange castValues = buildUnresolvedMaterialization(
+ MaterializationKind::Target, computeInsertPoint(repl), operandLoc,
+ /*valuesToMap=*/repl, /*inputs=*/repl, /*outputTypes=*/legalTypes,
+ /*originalType=*/origType, currentTypeConverter);
+ remapped.push_back(castValues);
}
return success();
}
@@ -1353,7 +1384,7 @@ Block *ConversionPatternRewriterImpl::applySignatureConversion(
buildUnresolvedMaterialization(
MaterializationKind::Source,
OpBuilder::InsertPoint(newBlock, newBlock->begin()), origArg.getLoc(),
- /*valueToMap=*/origArg, /*inputs=*/ValueRange(),
+ /*valuesToMap=*/{origArg}, /*inputs=*/ValueRange(),
/*outputType=*/origArgType, /*originalType=*/Type(), converter);
appendRewrite<ReplaceBlockArgRewrite>(block, origArg, converter);
continue;
@@ -1369,19 +1400,11 @@ Block *ConversionPatternRewriterImpl::applySignatureConversion(
continue;
}
- // This is a 1->1+ mapping. 1->N mappings are not fully supported in the
- // dialect conversion. Therefore, we need an argument materialization to
- // turn the replacement block arguments into a single SSA value that can be
- // used as a replacement.
+ // This is a 1->1+ mapping.
auto replArgs =
newBlock->getArguments().slice(inputMap->inputNo, inputMap->size);
- if (replArgs.size() == 1) {
- mapping.map(origArg, replArgs.front());
- } else {
- insertNTo1Materialization(
- OpBuilder::InsertPoint(newBlock, newBlock->begin()), origArg.getLoc(),
- /*replacements=*/replArgs, /*outputValue=*/origArg, converter);
- }
+ ValueVector replArgVals = llvm::to_vector_of<Value, 1>(replArgs);
+ mapping.map(origArg, std::move(replArgVals));
appendRewrite<ReplaceBlockArgRewrite>(block, origArg, converter);
}
@@ -1402,20 +1425,13 @@ Block *ConversionPatternRewriterImpl::applySignatureConversion(
/// of input operands.
ValueRange ConversionPatternRewriterImpl::buildUnresolvedMaterialization(
MaterializationKind kind, OpBuilder::InsertPoint ip, Location loc,
- Value valueToMap, ValueRange inputs, TypeRange outputTypes,
+ ValueVector valuesToMap, ValueRange inputs, TypeRange outputTypes,
Type originalType, const TypeConverter *converter,
UnrealizedConversionCastOp *castOp) {
assert((!originalType || kind == MaterializationKind::Target) &&
"original type is valid only for target materializations");
-
- // Avoid materializing an unnecessary cast.
- if (TypeRange(inputs) == outputTypes) {
- if (valueToMap) {
- assert(inputs.size() == 1 && "1:N mapping is not supported");
- mapping.map(valueToMap, inputs.front());
- }
- return inputs;
- }
+ assert(TypeRange(inputs) != outputTypes &&
+ "materialization is not necessary");
// Create an unresolved materialization. We use a new OpBuilder to avoid
// tracking the materialization like we do for other operations.
@@ -1423,37 +1439,23 @@ ValueRange ConversionPatternRewriterImpl::buildUnresolvedMaterialization(
builder.setInsertionPoint(ip.getBlock(), ip.getPoint());
auto convertOp =
builder.create<UnrealizedConversionCastOp>(loc, outputTypes, inputs);
- if (valueToMap) {
- assert(outputTypes.size() == 1 && "1:N mapping is not supported");
- mapping.map(valueToMap, convertOp.getResult(0));
- }
+ if (!valuesToMap.empty())
+ mapping.map(valuesToMap, convertOp.getResults());
if (castOp)
*castOp = convertOp;
- appendRewrite<UnresolvedMaterializationRewrite>(convertOp, converter, kind,
- originalType, valueToMap);
+ appendRewrite<UnresolvedMaterializationRewrite>(
+ convertOp, converter, kind, originalType, std::move(valuesToMap));
return convertOp.getResults();
}
-void ConversionPatternRewriterImpl::insertNTo1Materialization(
- OpBuilder::InsertPoint ip, Location loc, ValueRange replacements,
- Value originalValue, const TypeConverter *converter) {
- // Insert argument materialization back to the original type.
- Type originalType = originalValue.getType();
- UnrealizedConversionCastOp argCastOp;
- buildUnresolvedMaterialization(
- MaterializationKind::Argument, ip, loc, /*valueToMap=*/originalValue,
- /*inputs=*/replacements, originalType,
- /*originalType=*/Type(), converter, &argCastOp);
- if (argCastOp)
- nTo1TempMaterializations.insert(argCastOp);
-}
-
Value ConversionPatternRewriterImpl::findOrBuildReplacementValue(
Value value, const TypeConverter *converter) {
- // Find a replacement value with the same type.
- Value repl = mapping.lookupOrNull(value, value.getType());
- if (repl)
- return repl;
+ // Try to find a replacement value with the same type in the conversion value
+ // mapping. This includes cached materializations. We try to reuse those
+ // instead of generating duplicate IR.
+ ValueVector repl = mapping.lookupOrNull(value, value.getType());
+ if (!repl.empty())
+ return repl.front();
// Check if the value is dead. No replacement value is needed in that case.
// This is an approximate check that may have false negatives but does not
@@ -1468,7 +1470,7 @@ Value ConversionPatternRewriterImpl::findOrBuildReplacementValue(
// (regardless of the type) and build a source materialization to the
// original type.
repl = mapping.lookupOrNull(value);
- if (!repl) {
+ if (repl.empty()) {
// No replacement value is registered in the mapping. This means that the
// value is dropped and no longer needed. (If the value were still needed,
// a source materialization producing a replacement value "out of thin air"
@@ -1476,34 +1478,22 @@ Value ConversionPatternRewriterImpl::findOrBuildReplacementValue(
// `applySignatureConversion`.)
return Value();
}
- Value castValue = buildUnresolvedMaterialization(
- MaterializationKind::Source, computeInsertPoint(repl), value.getLoc(),
- /*valueToMap=*/value, /*inputs=*/repl, /*outputType=*/value.getType(),
- /*originalType=*/Type(), converter);
- mapping.map(value, castValue);
- return castValue;
-}
-SmallVector<Value>
-ConversionPatternRewriterImpl::unpackNTo1Materialization(Value value) {
- // Unpack unrealized_conversion_cast ops that were inserted as a N:1
- // workaround.
- auto castOp = value.getDefiningOp<UnrealizedConversionCastOp>();
- if (!castOp)
- return {value};
- if (!nTo1TempMaterializations.contains(castOp))
- return {value};
- assert(castOp->getNumResults() == 1 && "expected single result");
-
- SmallVector<Value> result;
- for (Value v : castOp.getOperands()) {
- // Keep unpacking if possible. This is needed because during block
- // signature conversions and 1:N op replacements, the driver may have
- // inserted two materializations back-to-back: first an argument
- // materialization, then a target materialization.
- llvm::append_range(result, unpackNTo1Materialization(v));
- }
- return result;
+ // Note: `computeInsertPoint` computes the "earliest" insertion point at
+ // which all values in `repl` are defined. It is important to emit the
+ // materialization at that location because the same materialization may be
+ // reused in a different context. (That's because materializations are cached
+ // in the conversion value mapping.) The insertion point of the
+ // materialization must be valid for all future users that may be created
+ // later in the conversion process.
+ Value castValue =
+ buildUnresolvedMaterialization(MaterializationKind::Source,
+ computeInsertPoint(repl), value.getLoc(),
+ /*valuesToMap=*/repl, /*inputs=*/repl,
+ /*outputType=*/value.getType(),
+ /*originalType=*/Type(), converter)
+ .front();
+ return castValue;
}
//===----------------------------------------------------------------------===//
@@ -1554,7 +1544,7 @@ void ConversionPatternRewriterImpl::notifyOpReplaced(
// Materialize a replacement value "out of thin air".
buildUnresolvedMaterialization(
MaterializationKind::Source, computeInsertPoint(result),
- result.getLoc(), /*valueToMap=*/result, /*inputs=*/ValueRange(),
+ result.getLoc(), /*valuesToMap=*/{result}, /*inputs=*/ValueRange(),
/*outputType=*/result.getType(), /*originalType=*/Type(),
currentTypeConverter);
continue;
@@ -1572,16 +1562,7 @@ void ConversionPatternRewriterImpl::notifyOpReplaced(
// Remap result to replacement value.
if (repl.empty())
continue;
-
- if (repl.size() == 1) {
- // Single replacement value: replace directly.
- mapping.map(result, repl.front());
- } else {
- // Multiple replacement values: insert N:1 materialization.
- insertNTo1Materialization(computeInsertPoint(result), result.getLoc(),
- /*replacements=*/repl, /*outputValue=*/result,
- currentTypeConverter);
- }
+ mapping.map(result, repl);
}
appendRewrite<ReplaceOperationRewrite>(op, currentTypeConverter);
@@ -1660,8 +1641,13 @@ void ConversionPatternRewriter::replaceOp(Operation *op, ValueRange newValues) {
<< "** Replace : '" << op->getName() << "'(" << op << ")\n";
});
SmallVector<ValueRange> newVals;
- for (size_t i = 0; i < newValues.size(); ++i)
- newVals.push_back(newValues.slice(i, 1));
+ for (size_t i = 0; i < newValues.size(); ++i) {
+ if (newValues[i]) {
+ newVals.push_back(newValues.slice(i, 1));
+ } else {
+ newVals.push_back(ValueRange());
+ }
+ }
impl->notifyOpReplaced(op, newVals);
}
@@ -1733,7 +1719,7 @@ void ConversionPatternRewriter::replaceUsesOfBlockArgument(BlockArgument from,
}
Value ConversionPatternRewriter::getRemappedValue(Value key) {
- SmallVector<SmallVector<Value>> remappedValues;
+ SmallVector<ValueVector> remappedValues;
if (failed(impl->remapValues("value", /*inputLoc=*/std::nullopt, *this, key,
remappedValues)))
return nullptr;
@@ -1746,7 +1732,7 @@ ConversionPatternRewriter::getRemappedValues(ValueRange keys,
SmallVectorImpl<Value> &results) {
if (keys.empty())
return success();
- SmallVector<SmallVector<Value>> remapped;
+ SmallVector<ValueVector> remapped;
if (failed(impl->remapValues("value", /*inputLoc=*/std::nullopt, *this, keys,
remapped)))
return failure();
@@ -1872,7 +1858,7 @@ ConversionPattern::matchAndRewrite(Operation *op,
getTypeConverter());
// Remap the operands of the operation.
- SmallVector<SmallVector<Value>> remapped;
+ SmallVector<ValueVector> remapped;
if (failed(rewriterImpl.remapValues("operand", op->getLoc(), rewriter,
op->getOperands(), remapped))) {
return failure();
@@ -2625,19 +2611,6 @@ legalizeUnresolvedMaterialization(RewriterBase &rewriter,
rewriter.setInsertionPoint(op);
SmallVector<Value> newMaterialization;
switch (rewrite->getMaterializationKind()) {
- case MaterializationKind::Argument: {
- // Try to materialize an argument conversion.
- assert(op->getNumResults() == 1 && "expected single result");
- Value argMat = converter->materializeArgumentConversion(
- rewriter, op->getLoc(), op.getResultTypes().front(), inputOperands);
- if (argMat) {
- newMaterialization.push_back(argMat);
- break;
- }
- }
- // If an argument materialization failed, fallback to trying a target
- // materialization.
- [[fallthrough]];
case MaterializationKind::Target:
newMaterialization = converter->materializeTargetConversion(
rewriter, op->getLoc(), op.getResultTypes(), inputOperands,
generated by cgit v1.1 at 2025-09-27 10:29:59 +0000