[Mlir-commits] [mlir] [mlir][emitc] Add 'emitc.while' and 'emitc.do' ops to the dialect (PR #143008)

Vlad Lazar llvmlistbot at llvm.org
Thu Jun 5 10:05:48 PDT 2025


https://github.com/Vladislave0-0 created https://github.com/llvm/llvm-project/pull/143008

This MR adds:
- 'emitc::WhileOp' and 'emitc::DoOp' to the EmitC dialect
- Emission of the corresponding ops in the CppEmitter
- Conversion from the SCF dialect to the EmitC dialect for the ops
- Corresponding tests

>From 61c29758819091d030df875742f829dc949cca27 Mon Sep 17 00:00:00 2001
From: Vlad Lazar <lazar_2004 at list.ru>
Date: Thu, 5 Jun 2025 19:41:52 +0300
Subject: [PATCH] [mlir][emitc] Add 'emitc.while' and 'emitc.do' ops to the
 dialect

This MR adds:
- 'emitc::WhileOp' and 'emitc::DoOp' to the EmitC dialect
- Emission of the corresponding ops in the CppEmitter
- Conversion from the SCF dialect to the EmitC dialect for the ops
- Corresponding tests
---
 mlir/include/mlir/Dialect/EmitC/IR/EmitC.td   | 154 +++++++++++-
 mlir/lib/Conversion/SCFToEmitC/SCFToEmitC.cpp | 238 +++++++++++++++++-
 mlir/lib/Dialect/EmitC/IR/EmitC.cpp           | 116 ++++++++-
 mlir/lib/Target/Cpp/TranslateToCpp.cpp        | 122 ++++++++-
 mlir/test/Conversion/SCFToEmitC/while.mlir    | 235 +++++++++++++++++
 mlir/test/Dialect/EmitC/invalid_ops.mlir      | 196 ++++++++++++++-
 mlir/test/Dialect/EmitC/ops.mlir              |  32 +++
 mlir/test/Target/Cpp/do.mlir                  |  69 +++++
 mlir/test/Target/Cpp/while.mlir               |  69 +++++
 9 files changed, 1214 insertions(+), 17 deletions(-)
 create mode 100644 mlir/test/Conversion/SCFToEmitC/while.mlir
 create mode 100644 mlir/test/Target/Cpp/do.mlir
 create mode 100644 mlir/test/Target/Cpp/while.mlir

diff --git a/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td b/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
index d4aea52a0d485..2390c4ef24cbc 100644
--- a/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
+++ b/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
@@ -1345,7 +1345,7 @@ def EmitC_AssignOp : EmitC_Op<"assign", []> {
 }
 
 def EmitC_YieldOp : EmitC_Op<"yield",
-      [Pure, Terminator, ParentOneOf<["ExpressionOp", "IfOp", "ForOp", "SwitchOp"]>]> {
+      [Pure, Terminator, ParentOneOf<["DoOp", "ExpressionOp", "ForOp", "IfOp", "SwitchOp", "WhileOp"]>]> {
   let summary = "Block termination operation";
   let description = [{
     The `emitc.yield` terminates its parent EmitC op's region, optionally yielding
@@ -1572,4 +1572,156 @@ def EmitC_SwitchOp : EmitC_Op<"switch", [RecursiveMemoryEffects,
   let hasVerifier = 1;
 }
 
+def EmitC_WhileOp : EmitC_Op<"while",
+      [HasOnlyGraphRegion, RecursiveMemoryEffects, NoRegionArguments, OpAsmOpInterface, NoTerminator]> {
+  let summary = "While operation";
+ let description = [{
+    The `emitc.while` operation represents a C/C++ while loop construct that
+    repeatedly executes a body region as long as a condition region evaluates to
+    true. The operation has two regions:
+    
+    1. A condition region that must yield a boolean value (i1) 
+    2. A body region that contains the loop body
+
+    The condition region is evaluated before each iteration. If it yields true,
+    the body region is executed. The loop terminates when the condition yields
+    false. The condition region must contain exactly one block that terminates
+    with an `emitc.yield` operation producing an i1 value.
+
+    Example:
+
+    ```mlir
+    emitc.func @foo(%arg0 : !emitc.ptr<i32>) {
+      %var = "emitc.variable"() <{value = 0 : i32}> : () -> !emitc.lvalue<i32>
+      %0 = emitc.literal "10" : i32
+      %1 = emitc.literal "1" : i32
+
+      emitc.while {
+        %var_load = load %var : <i32>
+        %res = emitc.cmp le, %var_load, %0 : (i32, i32) -> i1
+        emitc.yield %res : i1
+      } do {
+        emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+        %var_load = load %var : <i32>
+        %tmp_add = add %var_load, %1 : (i32, i32) -> i32
+        "emitc.assign"(%var, %tmp_add) : (!emitc.lvalue<i32>, i32) -> ()
+      }
+
+      return
+    }
+    ```
+
+    ```c++
+    // Code emitted for the operation above.
+    void foo(int32_t* v1) {
+      int32_t v2 = 0;
+      while (v2 <= 10) {
+        printf("%d", *v1);
+        int32_t v3 = v2;
+        int32_t v4 = v3 + 1;
+        v2 = v4;
+      }
+      return;
+    }
+    ```
+  }];
+
+  let arguments = (ins);
+  let results = (outs); 
+  let regions = (region MaxSizedRegion<1>:$conditionRegion,
+                        MaxSizedRegion<1>:$bodyRegion);
+
+  let hasCustomAssemblyFormat = 1;
+  let hasVerifier = 1;
+
+  let extraClassDeclaration = [{
+    Operation *getRootOp();
+
+    //===------------------------------------------------------------------===//
+    // OpAsmOpInterface Methods
+    //===------------------------------------------------------------------===//
+
+    /// EmitC ops in the body can omit their 'emitc.' prefix in the assembly.
+    static ::llvm::StringRef getDefaultDialect() {
+      return "emitc";
+    }
+  }];
+}
+
+def EmitC_DoOp : EmitC_Op<"do",
+      [RecursiveMemoryEffects, NoRegionArguments, OpAsmOpInterface, NoTerminator]> {
+  let summary = "Do-while operation";
+ let description = [{
+    The `emitc.do` operation represents a C/C++ do-while loop construct that
+    executes a body region first and then repeatedly executes it as long as a
+    condition region evaluates to true. The operation has two regions:
+
+    1. A body region that contains the loop body
+    2. A condition region that must yield a boolean value (i1)
+
+    Unlike a while loop, the body region is executed before the first evaluation
+    of the condition. The loop terminates when the condition yields false. The
+    condition region must contain exactly one block that terminates with an
+    `emitc.yield` operation producing an i1 value.
+
+    Example:
+
+    ```mlir
+    emitc.func @foo(%arg0 : !emitc.ptr<i32>) {
+      %var = "emitc.variable"() <{value = 0 : i32}> : () -> !emitc.lvalue<i32>
+      %0 = emitc.literal "10" : i32
+      %1 = emitc.literal "1" : i32
+
+      emitc.do {
+        emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+        %var_load = load %var : <i32>
+        %tmp_add = add %var_load, %1 : (i32, i32) -> i32
+        "emitc.assign"(%var, %tmp_add) : (!emitc.lvalue<i32>, i32) -> ()
+      } while {
+        %var_load = load %var : <i32>
+        %res = emitc.cmp le, %var_load, %0 : (i32, i32) -> i1
+        emitc.yield %res : i1
+      }
+
+      return
+    }
+    ```
+
+    ```c++
+    // Code emitted for the operation above.
+    void foo(int32_t* v1) {
+      int32_t v2 = 0;
+      do {
+        printf("%d", *v1);
+        int32_t v3 = v2;
+        int32_t v4 = v3 + 1;
+        v2 = v4;
+      } while (v2 <= 10);
+      return;
+    }
+    ```
+  }];
+
+  let arguments = (ins);
+  let results = (outs); 
+  let regions = (region MaxSizedRegion<1>:$bodyRegion,
+                        MaxSizedRegion<1>:$conditionRegion);
+
+  let hasCustomAssemblyFormat = 1;
+  let hasVerifier = 1;
+
+  let extraClassDeclaration = [{
+    Operation *getRootOp();
+
+    //===------------------------------------------------------------------===//
+    // OpAsmOpInterface Methods
+    //===------------------------------------------------------------------===//
+
+    /// EmitC ops in the body can omit their 'emitc.' prefix in the assembly.
+    static ::llvm::StringRef getDefaultDialect() {
+      return "emitc";
+    }
+  }];
+}
+
 #endif // MLIR_DIALECT_EMITC_IR_EMITC
diff --git a/mlir/lib/Conversion/SCFToEmitC/SCFToEmitC.cpp b/mlir/lib/Conversion/SCFToEmitC/SCFToEmitC.cpp
index 345e8494194eb..2e454070cb185 100644
--- a/mlir/lib/Conversion/SCFToEmitC/SCFToEmitC.cpp
+++ b/mlir/lib/Conversion/SCFToEmitC/SCFToEmitC.cpp
@@ -333,11 +333,246 @@ LogicalResult IndexSwitchOpLowering::matchAndRewrite(
   return success();
 }
 
+//==============================================================================
+
+// Lower scf::while to either emitc::while or emitc::do based on argument usage
+// patterns. Uses mutable variables to maintain loop state across iterations.
+struct WhileLowering : public OpConversionPattern<WhileOp> {
+  using OpConversionPattern::OpConversionPattern;
+
+  LogicalResult
+  matchAndRewrite(WhileOp whileOp, OpAdaptor adaptor,
+                  ConversionPatternRewriter &rewriter) const override {
+    Location loc = whileOp.getLoc();
+    MLIRContext *context = loc.getContext();
+
+    // Create variable storage for loop-carried values to enable imperative
+    // updates while maintaining SSA semantics at conversion boundaries.
+    SmallVector<Value> variables;
+    if (failed(
+            createInitVariables(whileOp, rewriter, variables, loc, context))) {
+      return failure();
+    }
+
+    // Select lowering strategy based on condition argument usage:
+    // - emitc.while when condition args match region inputs (direct mapping);
+    // - emitc.do when condition args differ (requires state synchronization).
+    Region &beforeRegion = adaptor.getBefore();
+    Block &beforeBlock = beforeRegion.front();
+    auto condOp = cast<scf::ConditionOp>(beforeRegion.back().getTerminator());
+
+    bool isDoOp = !llvm::equal(beforeBlock.getArguments(), condOp.getArgs());
+
+    LogicalResult result =
+        isDoOp ? lowerDoWhile(whileOp, variables, context, rewriter, loc)
+               : lowerWhile(whileOp, variables, context, rewriter, loc);
+
+    if (failed(result))
+      return failure();
+
+    // Create an emitc::variable op for each result. These variables will be
+    // assigned to by emitc::assign ops within the loop body.
+    SmallVector<Value> resultVariables;
+    if (failed(createVariablesForResults(whileOp, getTypeConverter(), rewriter,
+                                         resultVariables))) {
+      return rewriter.notifyMatchFailure(whileOp,
+                                         "Failed to create result variables");
+    }
+
+    rewriter.setInsertionPointAfter(whileOp);
+
+    // Transfer final loop state to result variables and get final SSA results.
+    SmallVector<Value> finalResults =
+        finalizeLoopResults(resultVariables, variables, rewriter, loc);
+
+    rewriter.replaceOp(whileOp, finalResults);
+    return success();
+  }
+
+private:
+  // Initialize variables for loop-carried values to enable state updates
+  // across iterations without SSA argument passing.
+  static LogicalResult createInitVariables(WhileOp whileOp,
+                                           ConversionPatternRewriter &rewriter,
+                                           SmallVectorImpl<Value> &outVars,
+                                           Location loc, MLIRContext *context) {
+    emitc::OpaqueAttr noInit = emitc::OpaqueAttr::get(context, "");
+
+    for (Value init : whileOp.getInits()) {
+      emitc::VariableOp var = rewriter.create<emitc::VariableOp>(
+          loc, emitc::LValueType::get(init.getType()), noInit);
+      rewriter.create<emitc::AssignOp>(loc, var.getResult(), init);
+      outVars.push_back(var.getResult());
+    }
+
+    return success();
+  }
+
+  // Transition from SSA block arguments to variable-based state management by
+  // replacing argument uses with variable loads and cleaning up block
+  // interface.
+  void replaceBlockArgsWithVarLoads(Block *block, ArrayRef<Value> vars,
+                                    ConversionPatternRewriter &rewriter,
+                                    Location loc) const {
+    rewriter.setInsertionPointToStart(block);
+
+    for (auto [arg, var] : llvm::zip(block->getArguments(), vars)) {
+      Type loadedType = cast<emitc::LValueType>(var.getType()).getValueType();
+      Value load = rewriter.create<emitc::LoadOp>(loc, loadedType, var);
+      arg.replaceAllUsesWith(load);
+    }
+
+    // Remove arguments after replacement to simplify block structure.
+    block->eraseArguments(0, block->getNumArguments());
+  }
+
+  // Convert SCF yield terminators to imperative assignments to update loop
+  // variables, maintaining loop semantics while transitioning to emitc model.
+  void processYieldTerminator(Operation *terminator, ArrayRef<Value> vars,
+                              ConversionPatternRewriter &rewriter,
+                              Location loc) const {
+    auto yieldOp = cast<scf::YieldOp>(terminator);
+    SmallVector<Value> yields(yieldOp.getOperands());
+    rewriter.eraseOp(yieldOp);
+
+    rewriter.setInsertionPointToEnd(yieldOp->getBlock());
+    for (auto [var, val] : llvm::zip(vars, yields))
+      rewriter.create<emitc::AssignOp>(loc, var, val);
+  }
+
+  // Transfers final loop state from mutable variables to result variables,
+  // then returns the final SSA values to replace the original scf::while
+  // results.
+  static SmallVector<Value>
+  finalizeLoopResults(ArrayRef<Value> resultVariables,
+                      ArrayRef<Value> loopVariables,
+                      ConversionPatternRewriter &rewriter, Location loc) {
+    // Transfer final loop state to result variables to bridge imperative loop
+    // variables with SSA result expectations of the original op.
+    for (auto [resultVar, var] : llvm::zip(resultVariables, loopVariables)) {
+      Type loadedType = cast<emitc::LValueType>(var.getType()).getValueType();
+      Value load = rewriter.create<emitc::LoadOp>(loc, loadedType, var);
+      rewriter.create<emitc::AssignOp>(loc, resultVar, load);
+    }
+
+    // Replace op with loaded values to integrate with converted SSA graph.
+    SmallVector<Value> finalResults;
+    for (Value resultVar : resultVariables) {
+      Type loadedType =
+          cast<emitc::LValueType>(resultVar.getType()).getValueType();
+      finalResults.push_back(
+          rewriter.create<emitc::LoadOp>(loc, loadedType, resultVar));
+    }
+
+    return finalResults;
+  }
+
+  // Direct lowering to emitc.while when condition arguments match region
+  // inputs.
+  LogicalResult lowerWhile(WhileOp whileOp, ArrayRef<Value> vars,
+                           MLIRContext *context,
+                           ConversionPatternRewriter &rewriter,
+                           Location loc) const {
+    auto loweredWhile = rewriter.create<emitc::WhileOp>(loc);
+
+    // Lower before region to condition region.
+    rewriter.inlineRegionBefore(whileOp.getBefore(),
+                                loweredWhile.getConditionRegion(),
+                                loweredWhile.getConditionRegion().end());
+
+    Block *condBlock = &loweredWhile.getConditionRegion().front();
+    replaceBlockArgsWithVarLoads(condBlock, vars, rewriter, loc);
+
+    Operation *condTerminator =
+        loweredWhile.getConditionRegion().back().getTerminator();
+    auto condOp = cast<scf::ConditionOp>(condTerminator);
+    rewriter.setInsertionPoint(condOp);
+    Value condition = rewriter.getRemappedValue(condOp.getCondition());
+    rewriter.create<emitc::YieldOp>(condOp.getLoc(), condition);
+    rewriter.eraseOp(condOp);
+
+    // Lower after region to body region.
+    rewriter.inlineRegionBefore(whileOp.getAfter(),
+                                loweredWhile.getBodyRegion(),
+                                loweredWhile.getBodyRegion().end());
+
+    Block *bodyBlock = &loweredWhile.getBodyRegion().front();
+    replaceBlockArgsWithVarLoads(bodyBlock, vars, rewriter, loc);
+
+    // Convert scf.yield to variable assignments for state updates.
+    processYieldTerminator(bodyBlock->getTerminator(), vars, rewriter, loc);
+
+    return success();
+  }
+
+  // Lower to emitc.do when condition arguments differ from region inputs.
+  LogicalResult lowerDoWhile(WhileOp whileOp, ArrayRef<Value> vars,
+                             MLIRContext *context,
+                             ConversionPatternRewriter &rewriter,
+                             Location loc) const {
+    Type i1Type = IntegerType::get(context, 1);
+    auto globalCondition =
+        rewriter.create<emitc::VariableOp>(loc, emitc::LValueType::get(i1Type),
+                                           emitc::OpaqueAttr::get(context, ""));
+    Value conditionVal = globalCondition.getResult();
+
+    auto loweredDo = rewriter.create<emitc::DoOp>(loc);
+
+    // Lower before region as body.
+    rewriter.inlineRegionBefore(whileOp.getBefore(), loweredDo.getBodyRegion(),
+                                loweredDo.getBodyRegion().end());
+
+    Block *bodyBlock = &loweredDo.getBodyRegion().front();
+    replaceBlockArgsWithVarLoads(bodyBlock, vars, rewriter, loc);
+
+    // Convert scf.condition to condition variable assignment.
+    Operation *condTerminator =
+        loweredDo.getBodyRegion().back().getTerminator();
+    scf::ConditionOp condOp = cast<scf::ConditionOp>(condTerminator);
+    rewriter.setInsertionPoint(condOp);
+    Value condition = rewriter.getRemappedValue(condOp.getCondition());
+    rewriter.create<emitc::AssignOp>(loc, conditionVal, condition);
+
+    // Wrap body region in conditional to preserve scf semantics.
+    auto ifOp = rewriter.create<emitc::IfOp>(loc, condition, false, false);
+
+    // Lower after region as then-block of conditional.
+    rewriter.inlineRegionBefore(whileOp.getAfter(), ifOp.getBodyRegion(),
+                                ifOp.getBodyRegion().begin());
+
+    if (!ifOp.getBodyRegion().empty()) {
+      Block *ifBlock = &ifOp.getBodyRegion().front();
+
+      // Handle argument mapping from condition op to body region.
+      auto args = condOp.getArgs();
+      for (auto [arg, val] : llvm::zip(ifBlock->getArguments(), args))
+        arg.replaceAllUsesWith(rewriter.getRemappedValue(val));
+
+      ifBlock->eraseArguments(0, ifBlock->getNumArguments());
+
+      // Convert scf.yield to variable assignments for state updates.
+      processYieldTerminator(ifBlock->getTerminator(), vars, rewriter, loc);
+      rewriter.create<emitc::YieldOp>(loc);
+    }
+
+    rewriter.eraseOp(condOp);
+
+    // Create condition region that loads from the flag variable.
+    Block *condBlock = rewriter.createBlock(&loweredDo.getConditionRegion());
+    rewriter.setInsertionPointToStart(condBlock);
+    Value cond = rewriter.create<emitc::LoadOp>(loc, i1Type, conditionVal);
+    rewriter.create<emitc::YieldOp>(loc, cond);
+
+    return success();
+  }
+};
+
 void mlir::populateSCFToEmitCConversionPatterns(RewritePatternSet &patterns,
                                                 TypeConverter &typeConverter) {
   patterns.add<ForLowering>(typeConverter, patterns.getContext());
   patterns.add<IfLowering>(typeConverter, patterns.getContext());
   patterns.add<IndexSwitchOpLowering>(typeConverter, patterns.getContext());
+  patterns.add<WhileLowering>(typeConverter, patterns.getContext());
 }
 
 void SCFToEmitCPass::runOnOperation() {
@@ -354,7 +589,8 @@ void SCFToEmitCPass::runOnOperation() {
 
   // Configure conversion to lower out SCF operations.
   ConversionTarget target(getContext());
-  target.addIllegalOp<scf::ForOp, scf::IfOp, scf::IndexSwitchOp>();
+  target
+      .addIllegalOp<scf::ForOp, scf::IfOp, scf::IndexSwitchOp, scf::WhileOp>();
   target.markUnknownOpDynamicallyLegal([](Operation *) { return true; });
   if (failed(
           applyPartialConversion(getOperation(), target, std::move(patterns))))
diff --git a/mlir/lib/Dialect/EmitC/IR/EmitC.cpp b/mlir/lib/Dialect/EmitC/IR/EmitC.cpp
index 1709654b90138..70a7150b818ff 100644
--- a/mlir/lib/Dialect/EmitC/IR/EmitC.cpp
+++ b/mlir/lib/Dialect/EmitC/IR/EmitC.cpp
@@ -900,10 +900,12 @@ LogicalResult emitc::YieldOp::verify() {
   Value result = getResult();
   Operation *containingOp = getOperation()->getParentOp();
 
-  if (result && containingOp->getNumResults() != 1)
+  if (result && containingOp->getNumResults() != 1 &&
+      !isa<WhileOp, DoOp>(containingOp))
     return emitOpError() << "yields a value not returned by parent";
 
-  if (!result && containingOp->getNumResults() != 0)
+  if (!result && containingOp->getNumResults() != 0 &&
+      !isa<WhileOp, DoOp>(containingOp))
     return emitOpError() << "does not yield a value to be returned by parent";
 
   return success();
@@ -1394,6 +1396,116 @@ void FileOp::build(OpBuilder &builder, OperationState &state, StringRef id) {
       builder.getNamedAttr("id", builder.getStringAttr(id)));
 }
 
+//===----------------------------------------------------------------------===//
+// Common functions for WhileOp and DoOp
+//===----------------------------------------------------------------------===//
+
+static Operation *getRootOpFromLoopCondition(Region &condRegion) {
+  auto yieldOp = cast<emitc::YieldOp>(condRegion.front().getTerminator());
+  return yieldOp.getResult().getDefiningOp();
+}
+
+static LogicalResult verifyLoopRegions(Operation &op, Region &condition,
+                                       Region &body) {
+  if (condition.empty())
+    return op.emitOpError("condition region cannot be empty");
+
+  Block &condBlock = condition.front();
+  for (Operation &inner : condBlock.without_terminator()) {
+    if (!inner.hasTrait<OpTrait::emitc::CExpression>())
+      return op.emitOpError(
+                 "expected all operations in condition region must implement "
+                 "CExpression trait, but ")
+             << inner.getName() << " does not";
+  }
+
+  auto condYield = dyn_cast<emitc::YieldOp>(condBlock.back());
+  if (!condYield)
+    return op.emitOpError(
+               "expected condition region to end with emitc.yield, but got ")
+           << condBlock.back().getName();
+
+  if (condYield.getNumOperands() != 1 ||
+      !condYield.getOperand(0).getType().isInteger(1))
+    return op.emitOpError("condition region must yield a single i1 value");
+
+  if (body.empty())
+    return op.emitOpError("body region cannot be empty");
+
+  Block &bodyBlock = body.front();
+  if (auto bodyYield = dyn_cast<emitc::YieldOp>(bodyBlock.back()))
+    if (bodyYield.getNumOperands() != 0)
+      return op.emitOpError(
+                 "expected body region to return 0 values, but body returns ")
+             << bodyYield.getNumOperands();
+
+  return success();
+}
+
+static void printLoop(OpAsmPrinter &p, Operation *self, Region &first,
+                      StringRef midKeyword, Region &second) {
+  p << ' ';
+  p.printRegion(first, /*printEntryBlockArgs=*/false);
+  p << ' ' << midKeyword << ' ';
+  p.printRegion(second);
+  p.printOptionalAttrDictWithKeyword(self->getAttrs());
+}
+
+static ParseResult parseLoop(OpAsmParser &parser, OperationState &res,
+                             StringRef midKeyword) {
+  Region *firstRegion = res.addRegion();
+  Region *secondRegion = res.addRegion();
+
+  if (parser.parseRegion(*firstRegion))
+    return failure();
+  if (parser.parseKeyword(midKeyword) || parser.parseRegion(*secondRegion))
+    return failure();
+
+  return parser.parseOptionalAttrDictWithKeyword(res.attributes);
+}
+
+//===----------------------------------------------------------------------===//
+// WhileOp
+//===----------------------------------------------------------------------===//
+
+Operation *WhileOp::getRootOp() {
+  return getRootOpFromLoopCondition(getConditionRegion());
+}
+
+void WhileOp::print(OpAsmPrinter &p) {
+  printLoop(p, getOperation(), getConditionRegion(), "do", getBodyRegion());
+}
+
+LogicalResult emitc::WhileOp::verify() {
+  return verifyLoopRegions(*getOperation(), getConditionRegion(),
+                           getBodyRegion());
+}
+
+ParseResult WhileOp::parse(OpAsmParser &parser, OperationState &result) {
+  return parseLoop(parser, result, "do");
+}
+
+//===----------------------------------------------------------------------===//
+// DoOp
+//===----------------------------------------------------------------------===//
+
+Operation *DoOp::getRootOp() {
+  return getRootOpFromLoopCondition(getConditionRegion());
+}
+
+void DoOp::print(OpAsmPrinter &p) {
+  printLoop(p, getOperation(), getBodyRegion(), "while", getConditionRegion());
+}
+
+LogicalResult emitc::DoOp::verify() {
+  return verifyLoopRegions(*getOperation(), getConditionRegion(),
+                           getBodyRegion());
+}
+
+ParseResult DoOp::parse(OpAsmParser &parser, OperationState &result) {
+  return parseLoop(parser, result, "while");
+}
+
 //===----------------------------------------------------------------------===//
 // TableGen'd op method definitions
 //===----------------------------------------------------------------------===//
diff --git a/mlir/lib/Target/Cpp/TranslateToCpp.cpp b/mlir/lib/Target/Cpp/TranslateToCpp.cpp
index 5abc112ab8c7a..18f25303a34b4 100644
--- a/mlir/lib/Target/Cpp/TranslateToCpp.cpp
+++ b/mlir/lib/Target/Cpp/TranslateToCpp.cpp
@@ -180,6 +180,12 @@ struct CppEmitter {
   /// Emit an expression as a C expression.
   LogicalResult emitExpression(ExpressionOp expressionOp);
 
+  /// Emit while as a C while.
+  LogicalResult emitWhile(WhileOp expressionOp);
+
+  /// Emit do-while as a C do-while.
+  LogicalResult emitDo(DoOp expressionOp);
+
   /// Insert the expression representing the operation into the value cache.
   void cacheDeferredOpResult(Value value, StringRef str);
 
@@ -198,6 +204,8 @@ struct CppEmitter {
   /// Return the existing or a new label of a Block.
   StringRef getOrCreateName(Block &block);
 
+  LogicalResult emitInlinedExpression(Value value);
+
   /// Whether to map an mlir integer to a unsigned integer in C++.
   bool shouldMapToUnsigned(IntegerType::SignednessSemantics val);
 
@@ -239,7 +247,7 @@ struct CppEmitter {
   }
 
   /// Get expression currently being emitted.
-  ExpressionOp getEmittedExpression() { return emittedExpression; }
+  Operation *getEmittedExpression() { return emittedExpression; }
 
   /// Determine whether given value is part of the expression potentially being
   /// emitted.
@@ -249,7 +257,8 @@ struct CppEmitter {
     Operation *def = value.getDefiningOp();
     if (!def)
       return false;
-    auto operandExpression = dyn_cast<ExpressionOp>(def->getParentOp());
+
+    Operation *operandExpression = def->getParentOp();
     return operandExpression == emittedExpression;
   };
 
@@ -280,7 +289,7 @@ struct CppEmitter {
   std::stack<int64_t> labelInScopeCount;
 
   /// State of the current expression being emitted.
-  ExpressionOp emittedExpression;
+  Operation *emittedExpression = nullptr;
   SmallVector<int> emittedExpressionPrecedence;
 
   void pushExpressionPrecedence(int precedence) {
@@ -510,6 +519,16 @@ static LogicalResult printOperation(CppEmitter &emitter,
   return success();
 }
 
+static LogicalResult printOperation(CppEmitter &emitter,
+                                    emitc::WhileOp whileOp) {
+  return emitter.emitWhile(whileOp);
+}
+
+static LogicalResult printOperation(CppEmitter &emitter,
+                                    emitc::DoOp doWhileOp) {
+  return emitter.emitDo(doWhileOp);
+}
+
 static LogicalResult printOperation(CppEmitter &emitter, emitc::CmpOp cmpOp) {
   Operation *operation = cmpOp.getOperation();
 
@@ -1424,6 +1443,84 @@ LogicalResult CppEmitter::emitExpression(ExpressionOp expressionOp) {
   return success();
 }
 
+LogicalResult CppEmitter::emitWhile(WhileOp whileOp) {
+  assert(emittedExpressionPrecedence.empty() &&
+         "Expected precedence stack to be empty");
+  Operation *rootOp = whileOp.getRootOp();
+
+  emittedExpression = whileOp;
+  FailureOr<int> precedence = getOperatorPrecedence(rootOp);
+  if (failed(precedence))
+    return failure();
+  pushExpressionPrecedence(precedence.value());
+
+  os << "while (";
+  if (failed(emitOperation(*rootOp, /*trailingSemicolon=*/false)))
+    return failure();
+  os << ") {\n";
+
+  popExpressionPrecedence();
+  assert(emittedExpressionPrecedence.empty() &&
+         "Expected precedence stack to be empty");
+  emittedExpression = nullptr;
+
+  os.indent();
+
+  Region &bodyRegion = whileOp.getBodyRegion();
+  auto regionOps = bodyRegion.getOps();
+
+  for (Operation &op : regionOps) {
+    if (isa<emitc::YieldOp>(op))
+      continue;
+
+    if (failed(emitOperation(op, /*trailingSemicolon=*/true)))
+      return failure();
+  }
+
+  os.unindent() << "}";
+
+  return success();
+}
+
+LogicalResult CppEmitter::emitDo(DoOp doWhileOp) {
+  os << "do {\n";
+  os.indent();
+
+  Region &bodyRegion = doWhileOp.getBodyRegion();
+  auto regionOps = bodyRegion.getOps();
+
+  for (Operation &op : regionOps) {
+    if (isa<emitc::YieldOp>(op))
+      continue;
+
+    if (failed(emitOperation(op, /*trailingSemicolon=*/true)))
+      return failure();
+  }
+
+  os.unindent() << "} while (";
+
+  assert(emittedExpressionPrecedence.empty() &&
+         "Expected precedence stack to be empty");
+  Operation *rootOp = doWhileOp.getRootOp();
+
+  emittedExpression = doWhileOp;
+  FailureOr<int> precedence = getOperatorPrecedence(rootOp);
+  if (failed(precedence))
+    return failure();
+  pushExpressionPrecedence(precedence.value());
+
+  if (failed(emitOperation(*rootOp, /*trailingSemicolon=*/false)))
+    return failure();
+  os << ");";
+
+  popExpressionPrecedence();
+  assert(emittedExpressionPrecedence.empty() &&
+         "Expected precedence stack to be empty");
+  emittedExpression = nullptr;
+
+  return success();
+}
+
 LogicalResult CppEmitter::emitOperand(Value value) {
   if (isPartOfCurrentExpression(value)) {
     Operation *def = value.getDefiningOp();
@@ -1607,12 +1704,13 @@ LogicalResult CppEmitter::emitOperation(Operation &op, bool trailingSemicolon) {
                 emitc::BitwiseRightShiftOp, emitc::BitwiseXorOp, emitc::CallOp,
                 emitc::CallOpaqueOp, emitc::CastOp, emitc::CmpOp,
                 emitc::ConditionalOp, emitc::ConstantOp, emitc::DeclareFuncOp,
-                emitc::DivOp, emitc::ExpressionOp, emitc::FileOp, emitc::ForOp,
-                emitc::FuncOp, emitc::GlobalOp, emitc::IfOp, emitc::IncludeOp,
-                emitc::LoadOp, emitc::LogicalAndOp, emitc::LogicalNotOp,
-                emitc::LogicalOrOp, emitc::MulOp, emitc::RemOp, emitc::ReturnOp,
-                emitc::SubOp, emitc::SwitchOp, emitc::UnaryMinusOp,
-                emitc::UnaryPlusOp, emitc::VariableOp, emitc::VerbatimOp>(
+                emitc::DivOp, emitc::DoOp, emitc::ExpressionOp, emitc::FileOp,
+                emitc::ForOp, emitc::FuncOp, emitc::GlobalOp, emitc::IfOp,
+                emitc::IncludeOp, emitc::LoadOp, emitc::LogicalAndOp,
+                emitc::LogicalNotOp, emitc::LogicalOrOp, emitc::MulOp,
+                emitc::RemOp, emitc::ReturnOp, emitc::SubOp, emitc::SwitchOp,
+                emitc::UnaryMinusOp, emitc::UnaryPlusOp, emitc::VariableOp,
+                emitc::VerbatimOp, emitc::WhileOp>(
 
               [&](auto op) { return printOperation(*this, op); })
           // Func ops.
@@ -1656,9 +1754,9 @@ LogicalResult CppEmitter::emitOperation(Operation &op, bool trailingSemicolon) {
   // Never emit a semicolon for some operations, especially if endening with
   // `}`.
   trailingSemicolon &=
-      !isa<cf::CondBranchOp, emitc::DeclareFuncOp, emitc::FileOp, emitc::ForOp,
-           emitc::IfOp, emitc::IncludeOp, emitc::SwitchOp, emitc::VerbatimOp>(
-          op);
+      !isa<cf::CondBranchOp, emitc::DeclareFuncOp, emitc::DoOp, emitc::FileOp,
+           emitc::ForOp, emitc::IfOp, emitc::IncludeOp, emitc::SwitchOp,
+           emitc::VerbatimOp, emitc::WhileOp>(op);
 
   os << (trailingSemicolon ? ";\n" : "\n");
 
diff --git a/mlir/test/Conversion/SCFToEmitC/while.mlir b/mlir/test/Conversion/SCFToEmitC/while.mlir
new file mode 100644
index 0000000000000..d4d64fac29280
--- /dev/null
+++ b/mlir/test/Conversion/SCFToEmitC/while.mlir
@@ -0,0 +1,235 @@
+// RUN: mlir-opt -allow-unregistered-dialect -convert-scf-to-emitc %s | FileCheck %s
+// RUN: mlir-opt -allow-unregistered-dialect -convert-to-emitc="filter-dialects=scf" %s | FileCheck %s
+
+emitc.func @payload_whileOp(%arg: i32) -> i32 {
+  %result = emitc.add %arg, %arg : (i32, i32) -> i32
+  return %result : i32
+}
+
+func.func @whileOp() -> i32 {
+  %init = emitc.literal "1.0" : i32
+  %var  = emitc.literal "1.0" : i32
+  %exit = emitc.literal "10.0" : i32
+
+  %res = scf.while (%arg1 = %init) : (i32) -> i32 {
+    %sum = emitc.add %arg1, %var : (i32, i32) -> i32
+    %condition = emitc.cmp lt, %sum, %exit : (i32, i32) -> i1
+    scf.condition(%condition) %arg1 : i32
+  } do {
+  ^bb0(%arg2: i32):
+    %next_arg1 = emitc.call @payload_whileOp(%arg2) : (i32) -> i32
+    scf.yield %next_arg1 : i32
+  }
+  
+  return %res : i32
+}
+// CHECK-LABEL:   emitc.func @payload_whileOp(
+// CHECK-SAME:      %[[ARG0:.*]]: i32) -> i32 {
+// CHECK:           %[[VAL_0:.*]] = add %[[ARG0]], %[[ARG0]] : (i32, i32) -> i32
+// CHECK:           return %[[VAL_0]] : i32
+// CHECK:         }
+
+// CHECK-LABEL:   func.func @whileOp() -> i32 {
+// CHECK:           %[[VAL_0:.*]] = emitc.literal "1.0" : i32
+// CHECK:           %[[VAL_1:.*]] = emitc.literal "1.0" : i32
+// CHECK:           %[[VAL_2:.*]] = emitc.literal "10.0" : i32
+// CHECK:           %[[VAL_3:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           emitc.assign %[[VAL_0]] : i32 to %[[VAL_3]] : <i32>
+// CHECK:           emitc.while {
+// CHECK:             %[[VAL_4:.*]] = load %[[VAL_3]] : <i32>
+// CHECK:             %[[VAL_5:.*]] = add %[[VAL_4]], %[[VAL_1]] : (i32, i32) -> i32
+// CHECK:             %[[VAL_6:.*]] = cmp lt, %[[VAL_5]], %[[VAL_2]] : (i32, i32) -> i1
+// CHECK:             yield %[[VAL_6]] : i1
+// CHECK:           } do {
+// CHECK:             %[[VAL_7:.*]] = load %[[VAL_3]] : <i32>
+// CHECK:             %[[VAL_8:.*]] = call @payload_whileOp(%[[VAL_7]]) : (i32) -> i32
+// CHECK:             assign %[[VAL_8]] : i32 to %[[VAL_3]] : <i32>
+// CHECK:           }
+// CHECK:           %[[VAL_9:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           %[[VAL_10:.*]] = emitc.load %[[VAL_3]] : <i32>
+// CHECK:           emitc.assign %[[VAL_10]] : i32 to %[[VAL_9]] : <i32>
+// CHECK:           %[[VAL_11:.*]] = emitc.load %[[VAL_9]] : <i32>
+// CHECK:           return %[[VAL_11]] : i32
+// CHECK:         }
+
+emitc.func @payload_doOp(%arg: i32) -> i32 {
+  %result = emitc.add %arg, %arg : (i32, i32) -> i32
+  return %result : i32
+}
+
+func.func @doOp() -> i32 {
+  %init = emitc.literal "1.0" : i32
+  %var  = emitc.literal "1.0" : i32
+  %exit = emitc.literal "10.0" : i32
+
+  %res = scf.while (%arg1 = %init) : (i32) -> i32 {
+    %sum = emitc.add %arg1, %var : (i32, i32) -> i32
+    %condition = emitc.cmp lt, %sum, %exit : (i32, i32) -> i1
+    %next = emitc.add %arg1, %arg1 : (i32, i32) -> i32
+    scf.condition(%condition) %next : i32
+  } do {
+  ^bb0(%arg2: i32):
+    %next_arg1 = emitc.call @payload_doOp(%arg2) : (i32) -> i32
+    scf.yield %next_arg1 : i32
+  }
+  
+  return %res : i32
+}
+// CHECK-LABEL:   emitc.func @payload_doOp(
+// CHECK-SAME:      %[[ARG0:.*]]: i32) -> i32 {
+// CHECK:           %[[VAL_0:.*]] = add %[[ARG0]], %[[ARG0]] : (i32, i32) -> i32
+// CHECK:           return %[[VAL_0]] : i32
+// CHECK:         }
+
+// CHECK-LABEL:   func.func @doOp() -> i32 {
+// CHECK:           %[[VAL_0:.*]] = emitc.literal "1.0" : i32
+// CHECK:           %[[VAL_1:.*]] = emitc.literal "1.0" : i32
+// CHECK:           %[[VAL_2:.*]] = emitc.literal "10.0" : i32
+// CHECK:           %[[VAL_3:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           emitc.assign %[[VAL_0]] : i32 to %[[VAL_3]] : <i32>
+// CHECK:           %[[VAL_4:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i1>
+// CHECK:           emitc.do {
+// CHECK:             %[[VAL_5:.*]] = load %[[VAL_3]] : <i32>
+// CHECK:             %[[VAL_6:.*]] = add %[[VAL_5]], %[[VAL_1]] : (i32, i32) -> i32
+// CHECK:             %[[VAL_7:.*]] = cmp lt, %[[VAL_6]], %[[VAL_2]] : (i32, i32) -> i1
+// CHECK:             %[[VAL_8:.*]] = add %[[VAL_5]], %[[VAL_5]] : (i32, i32) -> i32
+// CHECK:             assign %[[VAL_7]] : i1 to %[[VAL_4]] : <i1>
+// CHECK:             if %[[VAL_7]] {
+// CHECK:               %[[VAL_9:.*]] = call @payload_doOp(%[[VAL_8]]) : (i32) -> i32
+// CHECK:               assign %[[VAL_9]] : i32 to %[[VAL_3]] : <i32>
+// CHECK:             }
+// CHECK:           } while {
+// CHECK:             %[[VAL_10:.*]] = load %[[VAL_4]] : <i1>
+// CHECK:             yield %[[VAL_10]] : i1
+// CHECK:           }
+// CHECK:           %[[VAL_11:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           %[[VAL_12:.*]] = emitc.load %[[VAL_3]] : <i32>
+// CHECK:           emitc.assign %[[VAL_12]] : i32 to %[[VAL_11]] : <i32>
+// CHECK:           %[[VAL_13:.*]] = emitc.load %[[VAL_11]] : <i32>
+// CHECK:           return %[[VAL_13]] : i32
+// CHECK:         }
+
+emitc.func @payload_whileOp_two_results(%arg: i32) -> i32 {
+  %result = emitc.add %arg, %arg : (i32, i32) -> i32
+  return %result : i32
+}
+
+func.func @whileOp_two_results() -> i32 {
+  %init = emitc.literal "1.0" : i32
+  %exit = emitc.literal "10.0" : i32
+
+  %res1, %res2 = scf.while (%arg1_1 = %init, %arg1_2 = %init) : (i32, i32) -> (i32, i32) {
+    %sum = emitc.add %arg1_1, %arg1_2 : (i32, i32) -> i32
+    %condition = emitc.cmp lt, %sum, %exit : (i32, i32) -> i1
+    scf.condition(%condition) %arg1_1, %arg1_2  : i32, i32
+  } do {
+  ^bb0(%arg2_1 : i32, %arg2_2 : i32):
+    %next1 = emitc.call @payload_whileOp_two_results(%arg2_1) : (i32) -> i32
+    %next2 = emitc.call @payload_whileOp_two_results(%arg2_2) : (i32) -> i32
+    scf.yield %next1, %next2 : i32, i32
+  }
+  
+  return %res1 : i32
+}
+
+// CHECK-LABEL:   emitc.func @payload_whileOp_two_results(
+// CHECK-SAME:      %[[ARG0:.*]]: i32) -> i32 {
+// CHECK:           %[[VAL_0:.*]] = add %[[ARG0]], %[[ARG0]] : (i32, i32) -> i32
+// CHECK:           return %[[VAL_0]] : i32
+// CHECK:         }
+
+// CHECK-LABEL:   func.func @whileOp_two_results() -> i32 {
+// CHECK:           %[[VAL_0:.*]] = emitc.literal "1.0" : i32
+// CHECK:           %[[VAL_1:.*]] = emitc.literal "10.0" : i32
+// CHECK:           %[[VAL_2:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           emitc.assign %[[VAL_0]] : i32 to %[[VAL_2]] : <i32>
+// CHECK:           %[[VAL_3:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           emitc.assign %[[VAL_0]] : i32 to %[[VAL_3]] : <i32>
+// CHECK:           emitc.while {
+// CHECK:             %[[VAL_4:.*]] = load %[[VAL_2]] : <i32>
+// CHECK:             %[[VAL_5:.*]] = load %[[VAL_3]] : <i32>
+// CHECK:             %[[VAL_6:.*]] = add %[[VAL_4]], %[[VAL_5]] : (i32, i32) -> i32
+// CHECK:             %[[VAL_7:.*]] = cmp lt, %[[VAL_6]], %[[VAL_1]] : (i32, i32) -> i1
+// CHECK:             yield %[[VAL_7]] : i1
+// CHECK:           } do {
+// CHECK:             %[[VAL_8:.*]] = load %[[VAL_2]] : <i32>
+// CHECK:             %[[VAL_9:.*]] = load %[[VAL_3]] : <i32>
+// CHECK:             %[[VAL_10:.*]] = call @payload_whileOp_two_results(%[[VAL_8]]) : (i32) -> i32
+// CHECK:             %[[VAL_11:.*]] = call @payload_whileOp_two_results(%[[VAL_9]]) : (i32) -> i32
+// CHECK:             assign %[[VAL_10]] : i32 to %[[VAL_2]] : <i32>
+// CHECK:             assign %[[VAL_11]] : i32 to %[[VAL_3]] : <i32>
+// CHECK:           }
+// CHECK:           %[[VAL_12:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           %[[VAL_13:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           %[[VAL_14:.*]] = emitc.load %[[VAL_2]] : <i32>
+// CHECK:           emitc.assign %[[VAL_14]] : i32 to %[[VAL_12]] : <i32>
+// CHECK:           %[[VAL_15:.*]] = emitc.load %[[VAL_3]] : <i32>
+// CHECK:           emitc.assign %[[VAL_15]] : i32 to %[[VAL_13]] : <i32>
+// CHECK:           %[[VAL_16:.*]] = emitc.load %[[VAL_12]] : <i32>
+// CHECK:           %[[VAL_17:.*]] = emitc.load %[[VAL_13]] : <i32>
+// CHECK:           return %[[VAL_16]] : i32
+// CHECK:         }
+
+emitc.func @payload_doOp_two_results(%arg: i32) -> i32 {
+  %result = emitc.add %arg, %arg : (i32, i32) -> i32
+  return %result : i32
+}
+
+func.func @doOp_two_results() -> i32 {
+  %init = emitc.literal "1.0" : i32
+  %exit = emitc.literal "10.0" : i32
+
+  %res1, %res2 = scf.while (%arg1_1 = %init, %arg1_2 = %init) : (i32, i32) -> (i32, i32) {
+    %sum = emitc.add %arg1_1, %arg1_2 : (i32, i32) -> i32
+    %condition = emitc.cmp lt, %sum, %exit : (i32, i32) -> i1
+    scf.condition(%condition) %init, %arg1_2  : i32, i32
+  } do {
+  ^bb0(%arg2_1 : i32, %arg2_2 : i32):
+    %next1 = emitc.call @payload_doOp_two_results(%arg2_1) : (i32) -> i32
+    %next2 = emitc.call @payload_doOp_two_results(%arg2_2) : (i32) -> i32
+    scf.yield %next1, %next2 : i32, i32
+  }
+  
+  return %res1 : i32
+}
+
+// CHECK-LABEL:   emitc.func @payload_doOp_two_results(
+// CHECK-SAME:      %[[ARG0:.*]]: i32) -> i32 {
+// CHECK:           %[[VAL_0:.*]] = add %[[ARG0]], %[[ARG0]] : (i32, i32) -> i32
+// CHECK:           return %[[VAL_0]] : i32
+// CHECK:         }
+
+// CHECK-LABEL:   func.func @doOp_two_results() -> i32 {
+// CHECK:           %[[VAL_0:.*]] = emitc.literal "1.0" : i32
+// CHECK:           %[[VAL_1:.*]] = emitc.literal "10.0" : i32
+// CHECK:           %[[VAL_2:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           emitc.assign %[[VAL_0]] : i32 to %[[VAL_2]] : <i32>
+// CHECK:           %[[VAL_3:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           emitc.assign %[[VAL_0]] : i32 to %[[VAL_3]] : <i32>
+// CHECK:           %[[VAL_4:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i1>
+// CHECK:           emitc.do {
+// CHECK:             %[[VAL_5:.*]] = load %[[VAL_2]] : <i32>
+// CHECK:             %[[VAL_6:.*]] = load %[[VAL_3]] : <i32>
+// CHECK:             %[[VAL_7:.*]] = add %[[VAL_5]], %[[VAL_6]] : (i32, i32) -> i32
+// CHECK:             %[[VAL_8:.*]] = cmp lt, %[[VAL_7]], %[[VAL_1]] : (i32, i32) -> i1
+// CHECK:             assign %[[VAL_8]] : i1 to %[[VAL_4]] : <i1>
+// CHECK:             if %[[VAL_8]] {
+// CHECK:               %[[VAL_9:.*]] = call @payload_doOp_two_results(%[[VAL_0]]) : (i32) -> i32
+// CHECK:               %[[VAL_10:.*]] = call @payload_doOp_two_results(%[[VAL_6]]) : (i32) -> i32
+// CHECK:               assign %[[VAL_9]] : i32 to %[[VAL_2]] : <i32>
+// CHECK:               assign %[[VAL_10]] : i32 to %[[VAL_3]] : <i32>
+// CHECK:             }
+// CHECK:           } while {
+// CHECK:             %[[VAL_11:.*]] = load %[[VAL_4]] : <i1>
+// CHECK:             yield %[[VAL_11]] : i1
+// CHECK:           }
+// CHECK:           %[[VAL_12:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           %[[VAL_13:.*]] = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> !emitc.lvalue<i32>
+// CHECK:           %[[VAL_14:.*]] = emitc.load %[[VAL_2]] : <i32>
+// CHECK:           emitc.assign %[[VAL_14]] : i32 to %[[VAL_12]] : <i32>
+// CHECK:           %[[VAL_15:.*]] = emitc.load %[[VAL_3]] : <i32>
+// CHECK:           emitc.assign %[[VAL_15]] : i32 to %[[VAL_13]] : <i32>
+// CHECK:           %[[VAL_16:.*]] = emitc.load %[[VAL_12]] : <i32>
+// CHECK:           %[[VAL_17:.*]] = emitc.load %[[VAL_13]] : <i32>
+// CHECK:           return %[[VAL_16]] : i32
+// CHECK:         }
diff --git a/mlir/test/Dialect/EmitC/invalid_ops.mlir b/mlir/test/Dialect/EmitC/invalid_ops.mlir
index 3793dfe3f173b..acc8059658e34 100644
--- a/mlir/test/Dialect/EmitC/invalid_ops.mlir
+++ b/mlir/test/Dialect/EmitC/invalid_ops.mlir
@@ -252,7 +252,7 @@ func.func @sub_pointer_pointer(%arg0: !emitc.ptr<f32>, %arg1: !emitc.ptr<f32>) {
 // -----
 
 func.func @test_misplaced_yield() {
-  // expected-error @+1 {{'emitc.yield' op expects parent op to be one of 'emitc.expression, emitc.if, emitc.for, emitc.switch'}}
+  // expected-error @+1 {{'emitc.yield' op expects parent op to be one of 'emitc.do, emitc.expression, emitc.for, emitc.if, emitc.switch, emitc.while'}}
   emitc.yield
   return
 }
@@ -654,3 +654,197 @@ func.func @test_verbatim(%arg0 : !emitc.ptr<i32>, %arg1 : i32) {
   emitc.verbatim "{a} " args %arg0, %arg1 : !emitc.ptr<i32>, i32
   return
 }
+
+// -----
+
+func.func @test_while(%arg0 : !emitc.ptr<i32>) {
+  // expected-error @+1 {{'emitc.while' op condition region cannot be empty}}
+  emitc.while {
+  } do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  }
+
+  return
+}
+
+// -----
+
+emitc.func @test_while(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+
+  // expected-error @+1 {{'emitc.while' op expected all operations in condition region must implement CExpression trait, but emitc.literal does not}}
+  emitc.while {
+    %2 = emitc.literal "2" : i32
+    %3 = emitc.cmp eq, %1, %2 : (i32, i32) -> i1
+    emitc.yield %3 : i1
+  } do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  }
+
+  return
+}
+
+// -----
+
+func.func @test_while(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+
+  // expected-error @+1 {{'emitc.while' op expected condition region to end with emitc.yield, but got emitc.cmp}}
+  emitc.while {
+    %3 = emitc.cmp eq, %1, %2 : (i32, i32) -> i1
+  } do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  }
+
+  return
+}
+
+// -----
+
+func.func @test_while(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+
+  // expected-error @+1 {{'emitc.while' op condition region must yield a single i1 value}}
+  emitc.while {
+    %3 = emitc.add %1, %2 : (i32, i32) -> i32
+    emitc.yield %3 : i32
+  } do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  }
+
+  return
+}
+
+// -----
+
+func.func @test_while() {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+
+  // expected-error @+1 {{'emitc.while' op body region cannot be empty}}
+  emitc.while {
+    %3 = emitc.cmp eq, %1, %2 : (i32, i32) -> i1
+    emitc.yield %3 : i1
+  } do {
+  }
+
+  return
+}
+
+// -----
+
+emitc.func @test_while(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+
+  // expected-error @+1 {{'emitc.while' op expected body region to return 0 values, but body returns 1}}
+  emitc.while {
+    %3 = emitc.cmp eq, %1, %2 : (i32, i32) -> i1
+    emitc.yield %3 : i1
+  } do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+    %4 = emitc.add %1, %2 : (i32, i32) -> i32
+    emitc.yield %4 : i32
+  }
+
+  return
+}
+
+// -----
+
+func.func @test_do_while(%arg0 : !emitc.ptr<i32>) {
+  // expected-error @+1 {{'emitc.do' op condition region cannot be empty}}
+  emitc.do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  } while {
+  }
+
+  return
+}
+
+// -----
+
+emitc.func @test_do_while(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+
+  // expected-error @+1 {{'emitc.do' op expected all operations in condition region must implement CExpression trait, but emitc.literal does not}}
+  emitc.do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  } while {
+    %2 = emitc.literal "2" : i32
+    %3 = emitc.cmp eq, %1, %2 : (i32, i32) -> i1
+    emitc.yield %3 : i1
+  }
+
+  return
+}
+
+// -----
+
+func.func @test_do_while(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+
+  // expected-error @+1 {{'emitc.do' op expected condition region to end with emitc.yield, but got emitc.cmp}}
+  emitc.do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  } while {
+    %3 = emitc.cmp eq, %1, %2 : (i32, i32) -> i1
+  }
+
+  return
+}
+
+// -----
+
+func.func @test_do_while(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+
+  // expected-error @+1 {{'emitc.do' op condition region must yield a single i1 value}}
+  emitc.do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  } while {
+    %3 = emitc.add %1, %2 : (i32, i32) -> i32
+    emitc.yield %3 : i32
+  }
+
+  return
+}
+
+// -----
+
+func.func @test_do_while() {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+
+  // expected-error @+1 {{'emitc.do' op body region cannot be empty}}
+  emitc.do {
+  } while {
+    %3 = emitc.cmp eq, %1, %2 : (i32, i32) -> i1
+    emitc.yield %3 : i1
+  }
+
+  return
+}
+
+// -----
+
+emitc.func @test_do_while(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+
+  // expected-error @+1 {{'emitc.do' op expected body region to return 0 values, but body returns 1}}
+  emitc.do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+    %4 = emitc.add %1, %2 : (i32, i32) -> i32
+    emitc.yield %4 : i32
+  } while {
+    %3 = emitc.cmp eq, %1, %2 : (i32, i32) -> i1
+    emitc.yield %3 : i1
+  }
+
+  return
+}
diff --git a/mlir/test/Dialect/EmitC/ops.mlir b/mlir/test/Dialect/EmitC/ops.mlir
index 36d12e763afc7..739340f566dc4 100644
--- a/mlir/test/Dialect/EmitC/ops.mlir
+++ b/mlir/test/Dialect/EmitC/ops.mlir
@@ -302,3 +302,35 @@ func.func @switch() {
 
   return 
 }
+
+func.func @while(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+  %3 = emitc.literal "3" : i32
+
+  emitc.while {
+    %add = emitc.add %1, %2 : (i32, i32) -> i32
+    %5 = emitc.cmp eq, %add, %3 : (i32, i32) -> i1
+    emitc.yield %5 : i1
+  } do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  }
+
+  return
+}
+
+func.func @do(%arg0 : !emitc.ptr<i32>) {
+  %1 = emitc.literal "1" : i32
+  %2 = emitc.literal "2" : i32
+  %3 = emitc.literal "3" : i32
+
+  emitc.do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+  } while {
+    %add = emitc.add %1, %2 : (i32, i32) -> i32
+    %5 = emitc.cmp eq, %add, %3 : (i32, i32) -> i1
+    emitc.yield %5 : i1
+  }
+
+  return
+}
diff --git a/mlir/test/Target/Cpp/do.mlir b/mlir/test/Target/Cpp/do.mlir
new file mode 100644
index 0000000000000..034fe77ed22c4
--- /dev/null
+++ b/mlir/test/Target/Cpp/do.mlir
@@ -0,0 +1,69 @@
+// RUN: mlir-translate -mlir-to-cpp %s | FileCheck --match-full-lines %s -check-prefix=CPP-DEFAULT
+
+
+// CPP-DEFAULT-LABEL: void emitc_do(int32_t* v1) {
+// CPP-DEFAULT:         int32_t v2 = 0;
+// CPP-DEFAULT:         do {
+// CPP-DEFAULT:           printf("%d", *v1);
+// CPP-DEFAULT:           int32_t v3 = v2;
+// CPP-DEFAULT:           int32_t v4 = v3 + 1;
+// CPP-DEFAULT:           v2 = v4;
+// CPP-DEFAULT:         } while (v2 <= 10);
+// CPP-DEFAULT:         return;
+// CPP-DEFAULT:       }
+
+emitc.func @emitc_do(%arg0 : !emitc.ptr<i32>) {
+  %var = "emitc.variable"() <{value = 0 : i32}> : () -> !emitc.lvalue<i32>
+  %0 = emitc.literal "10" : i32
+  %1 = emitc.literal "1" : i32
+
+  emitc.do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+    %var_load = load %var : <i32>
+    %tmp_add = add %var_load, %1 : (i32, i32) -> i32
+    "emitc.assign"(%var, %tmp_add) : (!emitc.lvalue<i32>, i32) -> ()
+  } while {
+    %var_load = load %var : <i32>
+    %res = emitc.cmp le, %var_load, %0 : (i32, i32) -> i1
+    emitc.yield %res : i1
+  }
+
+  return
+}
+
+
+// CPP-DEFAULT-LABEL: void emitc_do_with_expression(int32_t* v1) {
+// CPP-DEFAULT:         int32_t v2 = 0;
+// CPP-DEFAULT:         int32_t v3 = 10 + 1;
+// CPP-DEFAULT:         do {
+// CPP-DEFAULT:           printf("%d", *v1);
+// CPP-DEFAULT:           int32_t v4 = v2;
+// CPP-DEFAULT:           int32_t v5 = v4 + 1;
+// CPP-DEFAULT:           v2 = v5;
+// CPP-DEFAULT:         } while (v2 <= v3);
+// CPP-DEFAULT:         return;
+// CPP-DEFAULT:       }
+
+emitc.func @emitc_do_with_expression(%arg0 : !emitc.ptr<i32>) {
+  %var = "emitc.variable"() <{value = 0 : i32}> : () -> !emitc.lvalue<i32>
+  %0 = emitc.literal "10" : i32
+  %1 = emitc.literal "1" : i32
+
+  %add = emitc.expression : i32 {
+    %add = add %0, %1 : (i32, i32) -> i32
+    yield %add : i32
+  }
+
+  emitc.do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+    %var_load = load %var : <i32>
+    %tmp_add = add %var_load, %1 : (i32, i32) -> i32
+    "emitc.assign"(%var, %tmp_add) : (!emitc.lvalue<i32>, i32) -> ()
+  } while {
+    %var_load = load %var : <i32>
+    %res = emitc.cmp le, %var_load, %add : (i32, i32) -> i1
+    emitc.yield %res : i1
+  }
+
+  return
+}
diff --git a/mlir/test/Target/Cpp/while.mlir b/mlir/test/Target/Cpp/while.mlir
new file mode 100644
index 0000000000000..76cf7c2f752cf
--- /dev/null
+++ b/mlir/test/Target/Cpp/while.mlir
@@ -0,0 +1,69 @@
+// RUN: mlir-translate -mlir-to-cpp %s | FileCheck --match-full-lines %s -check-prefix=CPP-DEFAULT
+
+
+// CPP-DEFAULT-LABEL: void emitc_while(int32_t* v1) {
+// CPP-DEFAULT:         int32_t v2 = 0;
+// CPP-DEFAULT:         while (v2 <= 10) {
+// CPP-DEFAULT:           printf("%d", *v1);
+// CPP-DEFAULT:           int32_t v3 = v2;
+// CPP-DEFAULT:           int32_t v4 = v3 + 1;
+// CPP-DEFAULT:           v2 = v4;
+// CPP-DEFAULT:         }
+// CPP-DEFAULT:         return;
+// CPP-DEFAULT:       }
+
+emitc.func @emitc_while(%arg0 : !emitc.ptr<i32>) {
+  %var = "emitc.variable"() <{value = 0 : i32}> : () -> !emitc.lvalue<i32>
+  %0 = emitc.literal "10" : i32
+  %1 = emitc.literal "1" : i32
+
+  emitc.while {
+    %var_load = load %var : <i32>
+    %res = emitc.cmp le, %var_load, %0 : (i32, i32) -> i1
+    emitc.yield %res : i1
+  } do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+    %var_load = load %var : <i32>
+    %tmp_add = add %var_load, %1 : (i32, i32) -> i32
+    "emitc.assign"(%var, %tmp_add) : (!emitc.lvalue<i32>, i32) -> ()
+  }
+
+  return
+}
+
+
+// CPP-DEFAULT-LABEL: void emitc_while_with_expression(int32_t* v1) {
+// CPP-DEFAULT:         int32_t v2 = 0;
+// CPP-DEFAULT:         int32_t v3 = 10 + 1;
+// CPP-DEFAULT:         while (v2 <= v3) {
+// CPP-DEFAULT:           printf("%d", *v1);
+// CPP-DEFAULT:           int32_t v4 = v2;
+// CPP-DEFAULT:           int32_t v5 = v4 + 1;
+// CPP-DEFAULT:           v2 = v5;
+// CPP-DEFAULT:         }
+// CPP-DEFAULT:         return;
+// CPP-DEFAULT:       }
+
+emitc.func @emitc_while_with_expression(%arg0 : !emitc.ptr<i32>) {
+  %var = "emitc.variable"() <{value = 0 : i32}> : () -> !emitc.lvalue<i32>
+  %0 = emitc.literal "10" : i32
+  %1 = emitc.literal "1" : i32
+
+  %add = emitc.expression : i32 {
+    %add = add %0, %1 : (i32, i32) -> i32
+    yield %add : i32
+  }
+
+  emitc.while {
+    %var_load = load %var : <i32>
+    %res = emitc.cmp le, %var_load, %add : (i32, i32) -> i1
+    emitc.yield %res : i1
+  } do {
+    emitc.verbatim "printf(\"%d\", *{});" args %arg0 : !emitc.ptr<i32>
+    %var_load = load %var : <i32>
+    %tmp_add = add %var_load, %1 : (i32, i32) -> i32
+    "emitc.assign"(%var, %tmp_add) : (!emitc.lvalue<i32>, i32) -> ()
+  }
+
+  return
+}



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