[Mlir-commits] [mlir] d980384 - [mlir][emitc] Add op modelling C expressions (#71631)

[llvmlistbot at llvm.org]

Author: Gil Rapaport
Date: 2023-12-20T15:04:46+02:00
New Revision: d9803841f2d539f6a740c07ebd0f3cb176812dbf

URL: https://github.com/llvm/llvm-project/commit/d9803841f2d539f6a740c07ebd0f3cb176812dbf
DIFF: https://github.com/llvm/llvm-project/commit/d9803841f2d539f6a740c07ebd0f3cb176812dbf.diff

LOG: [mlir][emitc] Add op modelling C expressions (#71631)

Add an emitc.expression operation that models C expressions, and provide
transforms to form and fold expressions. The translator emits the body
of
emitc.expression ops as a single C expression.
This expression is emitted by default as the RHS of an EmitC SSA value,
but if
possible, expressions with a single use that is not another expression
are
instead inlined. Specific expression's inlining can be fine tuned by
lowering
passes and transforms.

Added: 
    mlir/include/mlir/Dialect/EmitC/Transforms/CMakeLists.txt
    mlir/include/mlir/Dialect/EmitC/Transforms/Passes.h
    mlir/include/mlir/Dialect/EmitC/Transforms/Passes.td
    mlir/include/mlir/Dialect/EmitC/Transforms/Transforms.h
    mlir/lib/Dialect/EmitC/Transforms/CMakeLists.txt
    mlir/lib/Dialect/EmitC/Transforms/FormExpressions.cpp
    mlir/lib/Dialect/EmitC/Transforms/Transforms.cpp
    mlir/test/Dialect/EmitC/transforms.mlir
    mlir/test/Target/Cpp/expressions.mlir

Modified: 
    mlir/include/mlir/Dialect/EmitC/CMakeLists.txt
    mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
    mlir/include/mlir/InitAllPasses.h
    mlir/lib/Dialect/EmitC/CMakeLists.txt
    mlir/lib/Dialect/EmitC/IR/EmitC.cpp
    mlir/lib/Target/Cpp/TranslateToCpp.cpp
    mlir/test/Dialect/EmitC/invalid_ops.mlir
    mlir/test/Dialect/EmitC/ops.mlir
    mlir/test/Target/Cpp/for.mlir

Removed: 
    


################################################################################
diff  --git a/mlir/include/mlir/Dialect/EmitC/CMakeLists.txt b/mlir/include/mlir/Dialect/EmitC/CMakeLists.txt
index f33061b2d87cff..9f57627c321fb0 100644
--- a/mlir/include/mlir/Dialect/EmitC/CMakeLists.txt
+++ b/mlir/include/mlir/Dialect/EmitC/CMakeLists.txt
@@ -1 +1,2 @@
 add_subdirectory(IR)
+add_subdirectory(Transforms)

diff  --git a/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td b/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
index e09c63295515cb..b8f8f1e2d818d5 100644
--- a/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
+++ b/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
@@ -19,6 +19,7 @@ include "mlir/Dialect/EmitC/IR/EmitCTypes.td"
 include "mlir/Interfaces/CastInterfaces.td"
 include "mlir/Interfaces/ControlFlowInterfaces.td"
 include "mlir/Interfaces/SideEffectInterfaces.td"
+include "mlir/IR/RegionKindInterface.td"
 
 //===----------------------------------------------------------------------===//
 // EmitC op definitions
@@ -247,6 +248,83 @@ def EmitC_DivOp : EmitC_BinaryOp<"div", []> {
   let results = (outs FloatIntegerIndexOrOpaqueType);
 }
 
+def EmitC_ExpressionOp : EmitC_Op<"expression",
+      [HasOnlyGraphRegion, SingleBlockImplicitTerminator<"emitc::YieldOp">,
+       NoRegionArguments]> {
+  let summary = "Expression operation";
+  let description = [{
+    The `expression` operation returns a single SSA value which is yielded by
+    its single-basic-block region. The operation doesn't take any arguments.
+
+    As the operation is to be emitted as a C expression, the operations within
+    its body must form a single Def-Use tree of emitc ops whose result is
+    yielded by a terminating `yield`.
+
+    Example:
+
+    ```mlir
+    %r = emitc.expression : () -> i32 {
+      %0 = emitc.add %a, %b : (i32, i32) -> i32
+      %1 = emitc.call "foo"(%0) : () -> i32
+      %2 = emitc.add %c, %d : (i32, i32) -> i32
+      %3 = emitc.mul %1, %2 : (i32, i32) -> i32
+      yield %3
+    }
+    ```
+
+    May be emitted as
+
+    ```c++
+    int32_t v7 = foo(v1 + v2) * (v3 + v4);
+    ```
+
+    The operations allowed within expression body are emitc.add, emitc.apply,
+    emitc.call, emitc.cast, emitc.cmp, emitc.div, emitc.mul, emitc.rem and
+    emitc.sub.
+
+    When specified, the optional `do_not_inline` indicates that the expression is
+    to be emitted as seen above, i.e. as the rhs of an EmitC SSA value
+    definition. Otherwise, the expression may be emitted inline, i.e. directly
+    at its use.
+  }];
+
+  let arguments = (ins UnitAttr:$do_not_inline);
+  let results = (outs AnyType:$result);
+  let regions = (region SizedRegion<1>:$region);
+
+  let hasVerifier = 1;
+  let assemblyFormat = "attr-dict (`noinline` $do_not_inline^)? `:` type($result) $region";
+
+  let extraClassDeclaration = [{
+    static bool isCExpression(Operation &op) {
+      return isa<emitc::AddOp, emitc::ApplyOp, emitc::CallOpaqueOp,
+                 emitc::CastOp, emitc::CmpOp, emitc::DivOp, emitc::MulOp,
+                 emitc::RemOp, emitc::SubOp>(op);
+    }
+    bool hasSideEffects() {
+      auto predicate = [](Operation &op) {
+        assert(isCExpression(op) && "Expected a C expression");
+        // Conservatively assume calls to read and write memory.
+        if (isa<emitc::CallOpaqueOp>(op))
+          return true;
+        // De-referencing reads modifiable memory, address-taking has no
+        // side-effect.
+        auto applyOp = dyn_cast<emitc::ApplyOp>(op);
+        if (applyOp)
+          return applyOp.getApplicableOperator() == "*";
+        // Any operation using variables is assumed to have a side effect of
+        // reading memory mutable by emitc::assign ops.
+        return llvm::any_of(op.getOperands(), [](Value operand) {
+          Operation *def = operand.getDefiningOp();
+          return def && isa<emitc::VariableOp>(def);
+        });
+      };
+      return llvm::any_of(getRegion().front().without_terminator(), predicate);
+    };
+    Operation *getRootOp();
+  }];
+}
+
 def EmitC_ForOp : EmitC_Op<"for",
       [AllTypesMatch<["lowerBound", "upperBound", "step"]>,
        SingleBlockImplicitTerminator<"emitc::YieldOp">,
@@ -494,18 +572,24 @@ def EmitC_AssignOp : EmitC_Op<"assign", []> {
 }
 
 def EmitC_YieldOp : EmitC_Op<"yield",
-      [Pure, Terminator, ParentOneOf<["IfOp", "ForOp"]>]> {
+      [Pure, Terminator, ParentOneOf<["ExpressionOp", "IfOp", "ForOp"]>]> {
   let summary = "block termination operation";
   let description = [{
-    "yield" terminates blocks within EmitC control-flow operations. Since
-    control-flow constructs in C do not return values, this operation doesn't
-    take any arguments.
+    "yield" terminates its parent EmitC op's region, optionally yielding
+    an SSA value. The semantics of how the values are yielded is defined by the
+    parent operation.
+    If "yield" has an operand, the operand must match the parent operation's
+    result. If the parent operation defines no values, then the "emitc.yield"
+    may be left out in the custom syntax and the builders will insert one
+    implicitly. Otherwise, it has to be present in the syntax to indicate which
+    value is yielded.
   }];
 
-  let arguments = (ins);
+  let arguments = (ins Optional<AnyType>:$result);
   let builders = [OpBuilder<(ins), [{ /* nothing to do */ }]>];
 
-  let assemblyFormat = [{ attr-dict }];
+  let hasVerifier = 1;
+  let assemblyFormat = [{ attr-dict ($result^ `:` type($result))? }];
 }
 
 def EmitC_IfOp : EmitC_Op<"if",

diff  --git a/mlir/include/mlir/Dialect/EmitC/Transforms/CMakeLists.txt b/mlir/include/mlir/Dialect/EmitC/Transforms/CMakeLists.txt
new file mode 100644
index 00000000000000..0b507d75fa07a6
--- /dev/null
+++ b/mlir/include/mlir/Dialect/EmitC/Transforms/CMakeLists.txt
@@ -0,0 +1,5 @@
+set(LLVM_TARGET_DEFINITIONS Passes.td)
+mlir_tablegen(Passes.h.inc -gen-pass-decls -name EmitC)
+add_public_tablegen_target(MLIREmitCTransformsIncGen)
+
+add_mlir_doc(Passes EmitCPasses ./ -gen-pass-doc)

diff  --git a/mlir/include/mlir/Dialect/EmitC/Transforms/Passes.h b/mlir/include/mlir/Dialect/EmitC/Transforms/Passes.h
new file mode 100644
index 00000000000000..5cd27149d366ea
--- /dev/null
+++ b/mlir/include/mlir/Dialect/EmitC/Transforms/Passes.h
@@ -0,0 +1,35 @@
+//===- Passes.h - Pass Entrypoints ------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef MLIR_DIALECT_EMITC_TRANSFORMS_PASSES_H_
+#define MLIR_DIALECT_EMITC_TRANSFORMS_PASSES_H_
+
+#include "mlir/Pass/Pass.h"
+
+namespace mlir {
+namespace emitc {
+
+//===----------------------------------------------------------------------===//
+// Passes
+//===----------------------------------------------------------------------===//
+
+/// Creates an instance of the C-style expressions forming pass.
+std::unique_ptr<Pass> createFormExpressionsPass();
+
+//===----------------------------------------------------------------------===//
+// Registration
+//===----------------------------------------------------------------------===//
+
+/// Generate the code for registering passes.
+#define GEN_PASS_REGISTRATION
+#include "mlir/Dialect/EmitC/Transforms/Passes.h.inc"
+
+} // namespace emitc
+} // namespace mlir
+
+#endif // MLIR_DIALECT_EMITC_TRANSFORMS_PASSES_H_

diff  --git a/mlir/include/mlir/Dialect/EmitC/Transforms/Passes.td b/mlir/include/mlir/Dialect/EmitC/Transforms/Passes.td
new file mode 100644
index 00000000000000..fd083abc957157
--- /dev/null
+++ b/mlir/include/mlir/Dialect/EmitC/Transforms/Passes.td
@@ -0,0 +1,24 @@
+//===-- Passes.td - pass definition file -------------------*- tablegen -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef MLIR_DIALECT_EMITC_TRANSFORMS_PASSES
+#define MLIR_DIALECT_EMITC_TRANSFORMS_PASSES
+
+include "mlir/Pass/PassBase.td"
+
+def FormExpressions : Pass<"form-expressions"> {
+  let summary = "Form C-style expressions from C-operator ops";
+  let description = [{
+    The pass wraps emitc ops modelling C operators in emitc.expression ops and
+    then folds single-use expressions into their users where possible.
+  }];
+  let constructor = "mlir::emitc::createFormExpressionsPass()";
+  let dependentDialects = ["emitc::EmitCDialect"];
+}
+
+#endif // MLIR_DIALECT_EMITC_TRANSFORMS_PASSES

diff  --git a/mlir/include/mlir/Dialect/EmitC/Transforms/Transforms.h b/mlir/include/mlir/Dialect/EmitC/Transforms/Transforms.h
new file mode 100644
index 00000000000000..2574acd7d48e0b
--- /dev/null
+++ b/mlir/include/mlir/Dialect/EmitC/Transforms/Transforms.h
@@ -0,0 +1,34 @@
+//===- Transforms.h - EmitC transformations as patterns --------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef MLIR_DIALECT_EMITC_TRANSFORMS_TRANSFORMS_H
+#define MLIR_DIALECT_EMITC_TRANSFORMS_TRANSFORMS_H
+
+#include "mlir/Dialect/EmitC/IR/EmitC.h"
+#include "mlir/IR/PatternMatch.h"
+
+namespace mlir {
+namespace emitc {
+
+//===----------------------------------------------------------------------===//
+// Expression transforms
+//===----------------------------------------------------------------------===//
+
+ExpressionOp createExpression(Operation *op, OpBuilder &builder);
+
+//===----------------------------------------------------------------------===//
+// Populate functions
+//===----------------------------------------------------------------------===//
+
+/// Populates `patterns` with expression-related patterns.
+void populateExpressionPatterns(RewritePatternSet &patterns);
+
+} // namespace emitc
+} // namespace mlir
+
+#endif // MLIR_DIALECT_EMITC_TRANSFORMS_TRANSFORMS_H

diff  --git a/mlir/include/mlir/InitAllPasses.h b/mlir/include/mlir/InitAllPasses.h
index 311d93477d037e..28dc3cc23daf2b 100644
--- a/mlir/include/mlir/InitAllPasses.h
+++ b/mlir/include/mlir/InitAllPasses.h
@@ -23,6 +23,7 @@
 #include "mlir/Dialect/Async/Passes.h"
 #include "mlir/Dialect/Bufferization/Pipelines/Passes.h"
 #include "mlir/Dialect/Bufferization/Transforms/Passes.h"
+#include "mlir/Dialect/EmitC/Transforms/Passes.h"
 #include "mlir/Dialect/Func/Transforms/Passes.h"
 #include "mlir/Dialect/GPU/Pipelines/Passes.h"
 #include "mlir/Dialect/GPU/Transforms/Passes.h"
@@ -87,6 +88,7 @@ inline void registerAllPasses() {
   vector::registerVectorPasses();
   arm_sme::registerArmSMEPasses();
   arm_sve::registerArmSVEPasses();
+  emitc::registerEmitCPasses();
 
   // Dialect pipelines
   bufferization::registerBufferizationPipelines();

diff  --git a/mlir/lib/Dialect/EmitC/CMakeLists.txt b/mlir/lib/Dialect/EmitC/CMakeLists.txt
index f33061b2d87cff..9f57627c321fb0 100644
--- a/mlir/lib/Dialect/EmitC/CMakeLists.txt
+++ b/mlir/lib/Dialect/EmitC/CMakeLists.txt
@@ -1 +1,2 @@
 add_subdirectory(IR)
+add_subdirectory(Transforms)

diff  --git a/mlir/lib/Dialect/EmitC/IR/EmitC.cpp b/mlir/lib/Dialect/EmitC/IR/EmitC.cpp
index e8ea4da0b089c8..fd32efe783bcf5 100644
--- a/mlir/lib/Dialect/EmitC/IR/EmitC.cpp
+++ b/mlir/lib/Dialect/EmitC/IR/EmitC.cpp
@@ -189,6 +189,50 @@ LogicalResult emitc::ConstantOp::verify() {
 
 OpFoldResult emitc::ConstantOp::fold(FoldAdaptor adaptor) { return getValue(); }
 
+//===----------------------------------------------------------------------===//
+// ExpressionOp
+//===----------------------------------------------------------------------===//
+
+Operation *ExpressionOp::getRootOp() {
+  auto yieldOp = cast<YieldOp>(getBody()->getTerminator());
+  Value yieldedValue = yieldOp.getResult();
+  Operation *rootOp = yieldedValue.getDefiningOp();
+  assert(rootOp && "Yielded value not defined within expression");
+  return rootOp;
+}
+
+LogicalResult ExpressionOp::verify() {
+  Type resultType = getResult().getType();
+  Region &region = getRegion();
+
+  Block &body = region.front();
+
+  if (!body.mightHaveTerminator())
+    return emitOpError("must yield a value at termination");
+
+  auto yield = cast<YieldOp>(body.getTerminator());
+  Value yieldResult = yield.getResult();
+
+  if (!yieldResult)
+    return emitOpError("must yield a value at termination");
+
+  Type yieldType = yieldResult.getType();
+
+  if (resultType != yieldType)
+    return emitOpError("requires yielded type to match return type");
+
+  for (Operation &op : region.front().without_terminator()) {
+    if (!isCExpression(op))
+      return emitOpError("contains an unsupported operation");
+    if (op.getNumResults() != 1)
+      return emitOpError("requires exactly one result for each operation");
+    if (!op.getResult(0).hasOneUse())
+      return emitOpError("requires exactly one use for each operation");
+  }
+
+  return success();
+}
+
 //===----------------------------------------------------------------------===//
 // ForOp
 //===----------------------------------------------------------------------===//
@@ -530,6 +574,23 @@ LogicalResult emitc::VariableOp::verify() {
   return success();
 }
 
+//===----------------------------------------------------------------------===//
+// YieldOp
+//===----------------------------------------------------------------------===//
+
+LogicalResult emitc::YieldOp::verify() {
+  Value result = getResult();
+  Operation *containingOp = getOperation()->getParentOp();
+
+  if (result && containingOp->getNumResults() != 1)
+    return emitOpError() << "yields a value not returned by parent";
+
+  if (!result && containingOp->getNumResults() != 0)
+    return emitOpError() << "does not yield a value to be returned by parent";
+
+  return success();
+}
+
 //===----------------------------------------------------------------------===//
 // TableGen'd op method definitions
 //===----------------------------------------------------------------------===//

diff  --git a/mlir/lib/Dialect/EmitC/Transforms/CMakeLists.txt b/mlir/lib/Dialect/EmitC/Transforms/CMakeLists.txt
new file mode 100644
index 00000000000000..bfcc14523f137a
--- /dev/null
+++ b/mlir/lib/Dialect/EmitC/Transforms/CMakeLists.txt
@@ -0,0 +1,16 @@
+add_mlir_dialect_library(MLIREmitCTransforms
+  Transforms.cpp
+  FormExpressions.cpp
+
+  ADDITIONAL_HEADER_DIRS
+  ${MLIR_MAIN_INCLUDE_DIR}/mlir/Dialect/EmitC/Transforms
+
+  DEPENDS
+  MLIREmitCTransformsIncGen
+
+  LINK_LIBS PUBLIC
+  MLIRIR
+  MLIRPass
+  MLIREmitCDialect
+  MLIRTransforms
+)

diff  --git a/mlir/lib/Dialect/EmitC/Transforms/FormExpressions.cpp b/mlir/lib/Dialect/EmitC/Transforms/FormExpressions.cpp
new file mode 100644
index 00000000000000..21212155ffb22f
--- /dev/null
+++ b/mlir/lib/Dialect/EmitC/Transforms/FormExpressions.cpp
@@ -0,0 +1,60 @@
+//===- FormExpressions.cpp - Form C-style expressions --------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements a pass that forms EmitC operations modeling C operators
+// into C-style expressions using the emitc.expression op.
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Dialect/EmitC/IR/EmitC.h"
+#include "mlir/Dialect/EmitC/Transforms/Passes.h"
+#include "mlir/Dialect/EmitC/Transforms/Transforms.h"
+#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
+
+namespace mlir {
+namespace emitc {
+#define GEN_PASS_DEF_FORMEXPRESSIONS
+#include "mlir/Dialect/EmitC/Transforms/Passes.h.inc"
+} // namespace emitc
+} // namespace mlir
+
+using namespace mlir;
+using namespace emitc;
+
+namespace {
+struct FormExpressionsPass
+    : public emitc::impl::FormExpressionsBase<FormExpressionsPass> {
+  void runOnOperation() override {
+    Operation *rootOp = getOperation();
+    MLIRContext *context = rootOp->getContext();
+
+    // Wrap each C operator op with an expression op.
+    OpBuilder builder(context);
+    auto matchFun = [&](Operation *op) {
+      if (emitc::ExpressionOp::isCExpression(*op))
+        createExpression(op, builder);
+    };
+    rootOp->walk(matchFun);
+
+    // Fold expressions where possible.
+    RewritePatternSet patterns(context);
+    populateExpressionPatterns(patterns);
+
+    if (failed(applyPatternsAndFoldGreedily(rootOp, std::move(patterns))))
+      return signalPassFailure();
+  }
+
+  void getDependentDialects(DialectRegistry &registry) const override {
+    registry.insert<emitc::EmitCDialect>();
+  }
+};
+} // namespace
+
+std::unique_ptr<Pass> mlir::emitc::createFormExpressionsPass() {
+  return std::make_unique<FormExpressionsPass>();
+}

diff  --git a/mlir/lib/Dialect/EmitC/Transforms/Transforms.cpp b/mlir/lib/Dialect/EmitC/Transforms/Transforms.cpp
new file mode 100644
index 00000000000000..593d774cac73bd
--- /dev/null
+++ b/mlir/lib/Dialect/EmitC/Transforms/Transforms.cpp
@@ -0,0 +1,114 @@
+//===- Transforms.cpp - Patterns and transforms for the EmitC dialect -----===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Dialect/EmitC/Transforms/Transforms.h"
+#include "mlir/Dialect/EmitC/IR/EmitC.h"
+#include "mlir/IR/IRMapping.h"
+#include "mlir/IR/PatternMatch.h"
+#include "llvm/Support/Debug.h"
+
+namespace mlir {
+namespace emitc {
+
+ExpressionOp createExpression(Operation *op, OpBuilder &builder) {
+  assert(ExpressionOp::isCExpression(*op) && "Expected a C expression");
+
+  // Create an expression yielding the value returned by op.
+  assert(op->getNumResults() == 1 && "Expected exactly one result");
+  Value result = op->getResult(0);
+  Type resultType = result.getType();
+  Location loc = op->getLoc();
+
+  builder.setInsertionPointAfter(op);
+  auto expressionOp = builder.create<emitc::ExpressionOp>(loc, resultType);
+
+  // Replace all op's uses with the new expression's result.
+  result.replaceAllUsesWith(expressionOp.getResult());
+
+  // Create an op to yield op's value.
+  Region &region = expressionOp.getRegion();
+  Block &block = region.emplaceBlock();
+  builder.setInsertionPointToEnd(&block);
+  auto yieldOp = builder.create<emitc::YieldOp>(loc, result);
+
+  // Move op into the new expression.
+  op->moveBefore(yieldOp);
+
+  return expressionOp;
+}
+
+} // namespace emitc
+} // namespace mlir
+
+using namespace mlir;
+using namespace mlir::emitc;
+
+namespace {
+
+struct FoldExpressionOp : public OpRewritePattern<ExpressionOp> {
+  using OpRewritePattern<ExpressionOp>::OpRewritePattern;
+  LogicalResult matchAndRewrite(ExpressionOp expressionOp,
+                                PatternRewriter &rewriter) const override {
+    bool anythingFolded = false;
+    for (Operation &op : llvm::make_early_inc_range(
+             expressionOp.getBody()->without_terminator())) {
+      // Don't fold expressions whose result value has its address taken.
+      auto applyOp = dyn_cast<emitc::ApplyOp>(op);
+      if (applyOp && applyOp.getApplicableOperator() == "&")
+        continue;
+
+      for (Value operand : op.getOperands()) {
+        auto usedExpression =
+            dyn_cast_if_present<ExpressionOp>(operand.getDefiningOp());
+
+        if (!usedExpression)
+          continue;
+
+        // Don't fold expressions with multiple users: assume any
+        // re-materialization was done separately.
+        if (!usedExpression.getResult().hasOneUse())
+          continue;
+
+        // Don't fold expressions with side effects.
+        if (usedExpression.hasSideEffects())
+          continue;
+
+        // Fold the used expression into this expression by cloning all
+        // instructions in the used expression just before the operation using
+        // its value.
+        rewriter.setInsertionPoint(&op);
+        IRMapping mapper;
+        for (Operation &opToClone :
+             usedExpression.getBody()->without_terminator()) {
+          Operation *clone = rewriter.clone(opToClone, mapper);
+          mapper.map(&opToClone, clone);
+        }
+
+        Operation *expressionRoot = usedExpression.getRootOp();
+        Operation *clonedExpressionRootOp = mapper.lookup(expressionRoot);
+        assert(clonedExpressionRootOp &&
+               "Expected cloned expression root to be in mapper");
+        assert(clonedExpressionRootOp->getNumResults() == 1 &&
+               "Expected cloned root to have a single result");
+
+        Value clonedExpressionResult = clonedExpressionRootOp->getResult(0);
+
+        usedExpression.getResult().replaceAllUsesWith(clonedExpressionResult);
+        rewriter.eraseOp(usedExpression);
+        anythingFolded = true;
+      }
+    }
+    return anythingFolded ? success() : failure();
+  }
+};
+
+} // namespace
+
+void mlir::emitc::populateExpressionPatterns(RewritePatternSet &patterns) {
+  patterns.add<FoldExpressionOp>(patterns.getContext());
+}

diff  --git a/mlir/lib/Target/Cpp/TranslateToCpp.cpp b/mlir/lib/Target/Cpp/TranslateToCpp.cpp
index 1b4ec9eae93673..c32cb03caf9db6 100644
--- a/mlir/lib/Target/Cpp/TranslateToCpp.cpp
+++ b/mlir/lib/Target/Cpp/TranslateToCpp.cpp
@@ -15,6 +15,7 @@
 #include "mlir/IR/Dialect.h"
 #include "mlir/IR/Operation.h"
 #include "mlir/Support/IndentedOstream.h"
+#include "mlir/Support/LLVM.h"
 #include "mlir/Target/Cpp/CppEmitter.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/StringExtras.h"
@@ -65,6 +66,35 @@ inline LogicalResult interleaveCommaWithError(const Container &c,
   return interleaveWithError(c.begin(), c.end(), eachFn, [&]() { os << ", "; });
 }
 
+/// Return the precedence of a operator as an integer, higher values
+/// imply higher precedence.
+static int getOperatorPrecedence(Operation *operation) {
+  return llvm::TypeSwitch<Operation *, int>(operation)
+      .Case<emitc::AddOp>([&](auto op) { return 11; })
+      .Case<emitc::ApplyOp>([&](auto op) { return 13; })
+      .Case<emitc::CastOp>([&](auto op) { return 13; })
+      .Case<emitc::CmpOp>([&](auto op) {
+        switch (op.getPredicate()) {
+        case emitc::CmpPredicate::eq:
+        case emitc::CmpPredicate::ne:
+          return 8;
+        case emitc::CmpPredicate::lt:
+        case emitc::CmpPredicate::le:
+        case emitc::CmpPredicate::gt:
+        case emitc::CmpPredicate::ge:
+          return 9;
+        case emitc::CmpPredicate::three_way:
+          return 10;
+        }
+      })
+      .Case<emitc::DivOp>([&](auto op) { return 12; })
+      .Case<emitc::MulOp>([&](auto op) { return 12; })
+      .Case<emitc::RemOp>([&](auto op) { return 12; })
+      .Case<emitc::SubOp>([&](auto op) { return 11; })
+      .Case<emitc::CallOpaqueOp>([&](auto op) { return 14; });
+  llvm_unreachable("Unsupported operator");
+}
+
 namespace {
 /// Emitter that uses dialect specific emitters to emit C++ code.
 struct CppEmitter {
@@ -115,6 +145,12 @@ struct CppEmitter {
   /// Emits the operands of the operation. All operands are emitted in order.
   LogicalResult emitOperands(Operation &op);
 
+  /// Emits value as an operands of an operation
+  LogicalResult emitOperand(Value value);
+
+  /// Emit an expression as a C expression.
+  LogicalResult emitExpression(ExpressionOp expressionOp);
+
   /// Return the existing or a new name for a Value.
   StringRef getOrCreateName(Value val);
 
@@ -156,6 +192,21 @@ struct CppEmitter {
   /// be declared at the beginning of a function.
   bool shouldDeclareVariablesAtTop() { return declareVariablesAtTop; };
 
+  /// Get expression currently being emitted.
+  ExpressionOp getEmittedExpression() { return emittedExpression; }
+
+  /// Determine whether given value is part of the expression potentially being
+  /// emitted.
+  bool isPartOfCurrentExpression(Value value) {
+    if (!emittedExpression)
+      return false;
+    Operation *def = value.getDefiningOp();
+    if (!def)
+      return false;
+    auto operandExpression = dyn_cast<ExpressionOp>(def->getParentOp());
+    return operandExpression == emittedExpression;
+  };
+
 private:
   using ValueMapper = llvm::ScopedHashTable<Value, std::string>;
   using BlockMapper = llvm::ScopedHashTable<Block *, std::string>;
@@ -178,9 +229,50 @@ struct CppEmitter {
   /// names of values in a scope.
   std::stack<int64_t> valueInScopeCount;
   std::stack<int64_t> labelInScopeCount;
+
+  /// State of the current expression being emitted.
+  ExpressionOp emittedExpression;
+  SmallVector<int> emittedExpressionPrecedence;
+
+  void pushExpressionPrecedence(int precedence) {
+    emittedExpressionPrecedence.push_back(precedence);
+  }
+  void popExpressionPrecedence() { emittedExpressionPrecedence.pop_back(); }
+  static int lowestPrecedence() { return 0; }
+  int getExpressionPrecedence() {
+    if (emittedExpressionPrecedence.empty())
+      return lowestPrecedence();
+    return emittedExpressionPrecedence.back();
+  }
 };
 } // namespace
 
+/// Determine whether expression \p expressionOp should be emitted inline, i.e.
+/// as part of its user. This function recommends inlining of any expressions
+/// that can be inlined unless it is used by another expression, under the
+/// assumption that  any expression fusion/re-materialization was taken care of
+/// by transformations run by the backend.
+static bool shouldBeInlined(ExpressionOp expressionOp) {
+  // Do not inline if expression is marked as such.
+  if (expressionOp.getDoNotInline())
+    return false;
+
+  // Do not inline expressions with side effects to prevent side-effect
+  // reordering.
+  if (expressionOp.hasSideEffects())
+    return false;
+
+  // Do not inline expressions with multiple uses.
+  Value result = expressionOp.getResult();
+  if (!result.hasOneUse())
+    return false;
+
+  // Do not inline expressions used by other expressions, as any desired
+  // expression folding was taken care of by transformations.
+  Operation *user = *result.getUsers().begin();
+  return !user->getParentOfType<ExpressionOp>();
+}
+
 static LogicalResult printConstantOp(CppEmitter &emitter, Operation *operation,
                                      Attribute value) {
   OpResult result = operation->getResult(0);
@@ -253,9 +345,7 @@ static LogicalResult printOperation(CppEmitter &emitter,
   if (failed(emitter.emitVariableAssignment(result)))
     return failure();
 
-  emitter.ostream() << emitter.getOrCreateName(assignOp.getValue());
-
-  return success();
+  return emitter.emitOperand(assignOp.getValue());
 }
 
 static LogicalResult printBinaryOperation(CppEmitter &emitter,
@@ -265,9 +355,14 @@ static LogicalResult printBinaryOperation(CppEmitter &emitter,
 
   if (failed(emitter.emitAssignPrefix(*operation)))
     return failure();
-  os << emitter.getOrCreateName(operation->getOperand(0));
-  os << " " << binaryOperator;
-  os << " " << emitter.getOrCreateName(operation->getOperand(1));
+
+  if (failed(emitter.emitOperand(operation->getOperand(0))))
+    return failure();
+
+  os << " " << binaryOperator << " ";
+
+  if (failed(emitter.emitOperand(operation->getOperand(1))))
+    return failure();
 
   return success();
 }
@@ -485,9 +580,20 @@ static LogicalResult printOperation(CppEmitter &emitter, emitc::CastOp castOp) {
   if (failed(emitter.emitType(op.getLoc(), op.getResult(0).getType())))
     return failure();
   os << ") ";
-  os << emitter.getOrCreateName(castOp.getOperand());
+  return emitter.emitOperand(castOp.getOperand());
+}
 
-  return success();
+static LogicalResult printOperation(CppEmitter &emitter,
+                                    emitc::ExpressionOp expressionOp) {
+  if (shouldBeInlined(expressionOp))
+    return success();
+
+  Operation &op = *expressionOp.getOperation();
+
+  if (failed(emitter.emitAssignPrefix(op)))
+    return failure();
+
+  return emitter.emitExpression(expressionOp);
 }
 
 static LogicalResult printOperation(CppEmitter &emitter,
@@ -507,6 +613,17 @@ static LogicalResult printOperation(CppEmitter &emitter, emitc::ForOp forOp) {
 
   raw_indented_ostream &os = emitter.ostream();
 
+  // Utility function to determine whether a value is an expression that will be
+  // inlined, and as such should be wrapped in parentheses in order to guarantee
+  // its precedence and associativity.
+  auto requiresParentheses = [&](Value value) {
+    auto expressionOp =
+        dyn_cast_if_present<ExpressionOp>(value.getDefiningOp());
+    if (!expressionOp)
+      return false;
+    return shouldBeInlined(expressionOp);
+  };
+
   os << "for (";
   if (failed(
           emitter.emitType(forOp.getLoc(), forOp.getInductionVar().getType())))
@@ -514,15 +631,24 @@ static LogicalResult printOperation(CppEmitter &emitter, emitc::ForOp forOp) {
   os << " ";
   os << emitter.getOrCreateName(forOp.getInductionVar());
   os << " = ";
-  os << emitter.getOrCreateName(forOp.getLowerBound());
+  if (failed(emitter.emitOperand(forOp.getLowerBound())))
+    return failure();
   os << "; ";
   os << emitter.getOrCreateName(forOp.getInductionVar());
   os << " < ";
-  os << emitter.getOrCreateName(forOp.getUpperBound());
+  Value upperBound = forOp.getUpperBound();
+  bool upperBoundRequiresParentheses = requiresParentheses(upperBound);
+  if (upperBoundRequiresParentheses)
+    os << "(";
+  if (failed(emitter.emitOperand(upperBound)))
+    return failure();
+  if (upperBoundRequiresParentheses)
+    os << ")";
   os << "; ";
   os << emitter.getOrCreateName(forOp.getInductionVar());
   os << " += ";
-  os << emitter.getOrCreateName(forOp.getStep());
+  if (failed(emitter.emitOperand(forOp.getStep())))
+    return failure();
   os << ") {\n";
   os.indent();
 
@@ -557,7 +683,7 @@ static LogicalResult printOperation(CppEmitter &emitter, emitc::IfOp ifOp) {
   };
 
   os << "if (";
-  if (failed(emitter.emitOperands(*ifOp.getOperation())))
+  if (failed(emitter.emitOperand(ifOp.getCondition())))
     return failure();
   os << ") {\n";
   os.indent();
@@ -585,8 +711,10 @@ static LogicalResult printOperation(CppEmitter &emitter,
   case 0:
     return success();
   case 1:
-    os << " " << emitter.getOrCreateName(returnOp.getOperand(0));
-    return success(emitter.hasValueInScope(returnOp.getOperand(0)));
+    os << " ";
+    if (failed(emitter.emitOperand(returnOp.getOperand(0))))
+      return failure();
+    return success();
   default:
     os << " std::make_tuple(";
     if (failed(emitter.emitOperandsAndAttributes(*returnOp.getOperation())))
@@ -639,7 +767,10 @@ static LogicalResult printOperation(CppEmitter &emitter,
     // regions.
     WalkResult result =
         functionOp.walk<WalkOrder::PreOrder>([&](Operation *op) -> WalkResult {
-          if (isa<emitc::LiteralOp>(op))
+          if (isa<emitc::LiteralOp>(op) ||
+              isa<emitc::ExpressionOp>(op->getParentOp()) ||
+              (isa<emitc::ExpressionOp>(op) &&
+               shouldBeInlined(cast<emitc::ExpressionOp>(op))))
             return WalkResult::skip();
           for (OpResult result : op->getResults()) {
             if (failed(emitter.emitVariableDeclaration(
@@ -841,15 +972,70 @@ LogicalResult CppEmitter::emitAttribute(Location loc, Attribute attr) {
   return emitError(loc, "cannot emit attribute: ") << attr;
 }
 
+LogicalResult CppEmitter::emitExpression(ExpressionOp expressionOp) {
+  assert(emittedExpressionPrecedence.empty() &&
+         "Expected precedence stack to be empty");
+  Operation *rootOp = expressionOp.getRootOp();
+
+  emittedExpression = expressionOp;
+  pushExpressionPrecedence(getOperatorPrecedence(rootOp));
+
+  if (failed(emitOperation(*rootOp, /*trailingSemicolon=*/false)))
+    return failure();
+
+  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();
+    assert(def && "Expected operand to be defined by an operation");
+    int precedence = getOperatorPrecedence(def);
+    bool encloseInParenthesis = precedence < getExpressionPrecedence();
+    if (encloseInParenthesis) {
+      os << "(";
+      pushExpressionPrecedence(lowestPrecedence());
+    } else
+      pushExpressionPrecedence(precedence);
+
+    if (failed(emitOperation(*def, /*trailingSemicolon=*/false)))
+      return failure();
+
+    if (encloseInParenthesis)
+      os << ")";
+
+    popExpressionPrecedence();
+    return success();
+  }
+
+  auto expressionOp = dyn_cast_if_present<ExpressionOp>(value.getDefiningOp());
+  if (expressionOp && shouldBeInlined(expressionOp))
+    return emitExpression(expressionOp);
+
+  auto literalOp = dyn_cast_if_present<LiteralOp>(value.getDefiningOp());
+  if (!literalOp && !hasValueInScope(value))
+    return failure();
+  os << getOrCreateName(value);
+  return success();
+}
+
 LogicalResult CppEmitter::emitOperands(Operation &op) {
-  auto emitOperandName = [&](Value result) -> LogicalResult {
-    auto literalDef = dyn_cast_if_present<LiteralOp>(result.getDefiningOp());
-    if (!literalDef && !hasValueInScope(result))
-      return op.emitOpError() << "operand value not in scope";
-    os << getOrCreateName(result);
+  return interleaveCommaWithError(op.getOperands(), os, [&](Value operand) {
+    // If an expression is being emitted, push lowest precedence as these
+    // operands are either wrapped by parenthesis.
+    if (getEmittedExpression())
+      pushExpressionPrecedence(lowestPrecedence());
+    if (failed(emitOperand(operand)))
+      return failure();
+    if (getEmittedExpression())
+      popExpressionPrecedence();
     return success();
-  };
-  return interleaveCommaWithError(op.getOperands(), os, emitOperandName);
+  });
 }
 
 LogicalResult
@@ -902,6 +1088,10 @@ LogicalResult CppEmitter::emitVariableDeclaration(OpResult result,
 }
 
 LogicalResult CppEmitter::emitAssignPrefix(Operation &op) {
+  // If op is being emitted as part of an expression, bail out.
+  if (getEmittedExpression())
+    return success();
+
   switch (op.getNumResults()) {
   case 0:
     break;
@@ -952,9 +1142,9 @@ LogicalResult CppEmitter::emitOperation(Operation &op, bool trailingSemicolon) {
           // EmitC ops.
           .Case<emitc::AddOp, emitc::ApplyOp, emitc::AssignOp,
                 emitc::CallOpaqueOp, emitc::CastOp, emitc::CmpOp,
-                emitc::ConstantOp, emitc::DivOp, emitc::ForOp, emitc::IfOp,
-                emitc::IncludeOp, emitc::MulOp, emitc::RemOp, emitc::SubOp,
-                emitc::VariableOp>(
+                emitc::ConstantOp, emitc::DivOp, emitc::ExpressionOp,
+                emitc::ForOp, emitc::IfOp, emitc::IncludeOp, emitc::MulOp,
+                emitc::RemOp, emitc::SubOp, emitc::VariableOp>(
               [&](auto op) { return printOperation(*this, op); })
           // Func ops.
           .Case<func::CallOp, func::ConstantOp, func::FuncOp, func::ReturnOp>(
@@ -973,7 +1163,13 @@ LogicalResult CppEmitter::emitOperation(Operation &op, bool trailingSemicolon) {
   if (isa<emitc::LiteralOp>(op))
     return success();
 
+  if (getEmittedExpression() ||
+      (isa<emitc::ExpressionOp>(op) &&
+       shouldBeInlined(cast<emitc::ExpressionOp>(op))))
+    return success();
+
   os << (trailingSemicolon ? ";\n" : "\n");
+
   return success();
 }
 

diff  --git a/mlir/test/Dialect/EmitC/invalid_ops.mlir b/mlir/test/Dialect/EmitC/invalid_ops.mlir
index 49efb962dfa257..6ad646d7c62f11 100644
--- a/mlir/test/Dialect/EmitC/invalid_ops.mlir
+++ b/mlir/test/Dialect/EmitC/invalid_ops.mlir
@@ -203,7 +203,7 @@ 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.if, emitc.for'}}
+  // expected-error @+1 {{'emitc.yield' op expects parent op to be one of 'emitc.expression, emitc.if, emitc.for'}}
   emitc.yield
   return
 }
@@ -224,3 +224,60 @@ func.func @test_assign_type_mismatch(%arg1: f32) {
   emitc.assign %arg1 : f32 to %v : i32
   return
 }
+
+// -----
+
+func.func @test_expression_no_yield() -> i32 {
+  // expected-error @+1 {{'emitc.expression' op must yield a value at termination}}
+  %r = emitc.expression : i32 {
+    %c7 = "emitc.constant"(){value = 7 : i32} : () -> i32
+  }
+  return %r : i32
+}
+
+// -----
+
+func.func @test_expression_illegal_op(%arg0 : i1) -> i32 {
+  // expected-error @+1 {{'emitc.expression' op contains an unsupported operation}}
+  %r = emitc.expression : i32 {
+    %x = "emitc.variable"() <{value = #emitc.opaque<"">}> : () -> i32
+    emitc.yield %x : i32
+  }
+  return %r : i32
+}
+
+// -----
+
+func.func @test_expression_no_use(%arg0: i32, %arg1: i32) -> i32 {
+  // expected-error @+1 {{'emitc.expression' op requires exactly one use for each operation}}
+  %r = emitc.expression : i32 {
+    %a = emitc.add %arg0, %arg1 : (i32, i32) -> i32
+    %b = emitc.rem %arg0, %arg1 : (i32, i32) -> i32
+    emitc.yield %a : i32
+  }
+  return %r : i32
+}
+
+// -----
+
+func.func @test_expression_multiple_uses(%arg0: i32, %arg1: i32) -> i32 {
+  // expected-error @+1 {{'emitc.expression' op requires exactly one use for each operation}}
+  %r = emitc.expression : i32 {
+    %a = emitc.rem %arg0, %arg1 : (i32, i32) -> i32
+    %b = emitc.add %a, %arg0 : (i32, i32) -> i32
+    %c = emitc.mul %arg1, %a : (i32, i32) -> i32
+    emitc.yield %a : i32
+  }
+  return %r : i32
+}
+
+// -----
+
+func.func @test_expression_multiple_results(%arg0: i32) -> i32 {
+  // expected-error @+1 {{'emitc.expression' op requires exactly one result for each operation}}
+  %r = emitc.expression : i32 {
+    %a:2 = emitc.call_opaque "bar" (%arg0) : (i32) -> (i32, i32)
+    emitc.yield %a : i32
+  }
+  return %r : i32
+}

diff  --git a/mlir/test/Dialect/EmitC/ops.mlir b/mlir/test/Dialect/EmitC/ops.mlir
index b3a24c26b96cab..45ce2bcb99092c 100644
--- a/mlir/test/Dialect/EmitC/ops.mlir
+++ b/mlir/test/Dialect/EmitC/ops.mlir
@@ -128,6 +128,23 @@ func.func @test_assign(%arg1: f32) {
   return
 }
 
+func.func @test_expression(%arg0: i32, %arg1: i32, %arg2: i32, %arg3: f32, %arg4: f32) -> i32 {
+  %c7 = "emitc.constant"() {value = 7 : i32} : () -> i32
+  %q = emitc.expression : i32 {
+    %a = emitc.rem %arg1, %c7 : (i32, i32) -> i32
+    emitc.yield %a : i32
+  }
+  %r = emitc.expression noinline : i32 {
+    %a = emitc.add %arg0, %arg1 : (i32, i32) -> i32
+    %b = emitc.call_opaque "bar" (%a, %arg2, %q) : (i32, i32, i32) -> (i32)
+    %c = emitc.mul %arg3, %arg4 : (f32, f32) -> f32
+    %d = emitc.cast %c : f32 to i32
+    %e = emitc.sub %b, %d : (i32, i32) -> i32
+    emitc.yield %e : i32
+  }
+  return %r : i32
+}
+
 func.func @test_for(%arg0 : index, %arg1 : index, %arg2 : index) {
   emitc.for %i0 = %arg0 to %arg1 step %arg2 {
     %0 = emitc.call_opaque "func_const"(%i0) : (index) -> i32

diff  --git a/mlir/test/Dialect/EmitC/transforms.mlir b/mlir/test/Dialect/EmitC/transforms.mlir
new file mode 100644
index 00000000000000..ad167fa455a1a5
--- /dev/null
+++ b/mlir/test/Dialect/EmitC/transforms.mlir
@@ -0,0 +1,109 @@
+// RUN: mlir-opt %s --form-expressions --verify-diagnostics --split-input-file | FileCheck %s
+
+// CHECK-LABEL: func.func @single_expression(
+// CHECK-SAME:                               %[[VAL_0:.*]]: i32, %[[VAL_1:.*]]: i32, %[[VAL_2:.*]]: i32, %[[VAL_3:.*]]: i32) -> i1 {
+// CHECK:           %[[VAL_4:.*]] = "emitc.constant"() <{value = 42 : i32}> : () -> i32
+// CHECK:           %[[VAL_5:.*]] = emitc.expression : i1 {
+// CHECK:             %[[VAL_6:.*]] = emitc.mul %[[VAL_0]], %[[VAL_4]] : (i32, i32) -> i32
+// CHECK:             %[[VAL_7:.*]] = emitc.sub %[[VAL_6]], %[[VAL_2]] : (i32, i32) -> i32
+// CHECK:             %[[VAL_8:.*]] = emitc.cmp lt, %[[VAL_7]], %[[VAL_3]] : (i32, i32) -> i1
+// CHECK:             emitc.yield %[[VAL_8]] : i1
+// CHECK:           }
+// CHECK:           return %[[VAL_5]] : i1
+// CHECK:       }
+
+func.func @single_expression(%arg0: i32, %arg1: i32, %arg2: i32, %arg3: i32) -> i1 {
+  %c42 = "emitc.constant"(){value = 42 : i32} : () -> i32
+  %a = emitc.mul %arg0, %c42 : (i32, i32) -> i32
+  %b = emitc.sub %a, %arg2 : (i32, i32) -> i32
+  %c = emitc.cmp lt, %b, %arg3 :(i32, i32) -> i1
+  return %c : i1
+}
+
+// CHECK-LABEL: func.func @multiple_expressions(
+// CHECK-SAME:      %[[VAL_0:.*]]: i32, %[[VAL_1:.*]]: i32, %[[VAL_2:.*]]: i32, %[[VAL_3:.*]]: i32) -> (i32, i32) {
+// CHECK:         %[[VAL_4:.*]] = emitc.expression : i32 {
+// CHECK:           %[[VAL_5:.*]] = emitc.mul %[[VAL_0]], %[[VAL_1]] : (i32, i32) -> i32
+// CHECK:           %[[VAL_6:.*]] = emitc.sub %[[VAL_5]], %[[VAL_2]] : (i32, i32) -> i32
+// CHECK:           emitc.yield %[[VAL_6]] : i32
+// CHECK:         }
+// CHECK:         %[[VAL_7:.*]] = emitc.expression : i32 {
+// CHECK:           %[[VAL_8:.*]] = emitc.add %[[VAL_1]], %[[VAL_3]] : (i32, i32) -> i32
+// CHECK:           %[[VAL_9:.*]] = emitc.div %[[VAL_8]], %[[VAL_2]] : (i32, i32) -> i32
+// CHECK:           emitc.yield %[[VAL_9]] : i32
+// CHECK:         }
+// CHECK:         return %[[VAL_4]], %[[VAL_7]] : i32, i32
+// CHECK:       }
+
+func.func @multiple_expressions(%arg0: i32, %arg1: i32, %arg2: i32, %arg3: i32) -> (i32, i32) {
+  %a = emitc.mul %arg0, %arg1 : (i32, i32) -> i32
+  %b = emitc.sub %a, %arg2 : (i32, i32) -> i32
+  %c = emitc.add %arg1, %arg3 : (i32, i32) -> i32
+  %d = emitc.div %c, %arg2 : (i32, i32) -> i32
+  return %b, %d : i32, i32
+}
+
+// CHECK-LABEL: func.func @expression_with_call(
+// CHECK-SAME:      %[[VAL_0:.*]]: i32, %[[VAL_1:.*]]: i32, %[[VAL_2:.*]]: i32, %[[VAL_3:.*]]: i32) -> i1 {
+// CHECK:         %[[VAL_4:.*]] = emitc.expression : i32 {
+// CHECK:           %[[VAL_5:.*]] = emitc.mul %[[VAL_0]], %[[VAL_1]] : (i32, i32) -> i32
+// CHECK:           %[[VAL_6:.*]] = emitc.call_opaque "foo"(%[[VAL_5]], %[[VAL_2]]) : (i32, i32) -> i32
+// CHECK:           emitc.yield %[[VAL_6]] : i32
+// CHECK:         }
+// CHECK:         %[[VAL_7:.*]] = emitc.expression : i1 {
+// CHECK:           %[[VAL_8:.*]] = emitc.cmp lt, %[[VAL_4]], %[[VAL_1]] : (i32, i32) -> i1
+// CHECK:           emitc.yield %[[VAL_8]] : i1
+// CHECK:         }
+// CHECK:         return %[[VAL_7]] : i1
+// CHECK:       }
+
+func.func @expression_with_call(%arg0: i32, %arg1: i32, %arg2: i32, %arg3: i32) -> i1 {
+  %a = emitc.mul %arg0, %arg1 : (i32, i32) -> i32
+  %b = emitc.call_opaque "foo" (%a, %arg2) : (i32, i32) -> (i32)
+  %c = emitc.cmp lt, %b, %arg1 :(i32, i32) -> i1
+  return %c : i1
+}
+
+// CHECK-LABEL: func.func @expression_with_dereference(
+// CHECK-SAME:      %[[VAL_0:.*]]: i32, %[[VAL_1:.*]]: i32, %[[VAL_2:.*]]: !emitc.ptr<i32>) -> i1 {
+// CHECK:         %[[VAL_3:.*]] = emitc.expression : i32 {
+// CHECK:           %[[VAL_4:.*]] = emitc.apply "*"(%[[VAL_2]]) : (!emitc.ptr<i32>) -> i32
+// CHECK:           emitc.yield %[[VAL_4]] : i32
+// CHECK:         }
+// CHECK:         %[[VAL_5:.*]] = emitc.expression : i1 {
+// CHECK:           %[[VAL_6:.*]] = emitc.mul %[[VAL_0]], %[[VAL_1]] : (i32, i32) -> i32
+// CHECK:           %[[VAL_7:.*]] = emitc.cmp lt, %[[VAL_6]], %[[VAL_3]] : (i32, i32) -> i1
+// CHECK:           emitc.yield %[[VAL_7]] : i1
+// CHECK:         }
+// CHECK:         return %[[VAL_5]] : i1
+// CHECK:       }
+
+func.func @expression_with_dereference(%arg0: i32, %arg1: i32, %arg2: !emitc.ptr<i32>) -> i1 {
+  %a = emitc.mul %arg0, %arg1 : (i32, i32) -> i32
+  %b = emitc.apply "*"(%arg2) : (!emitc.ptr<i32>) -> (i32)
+  %c = emitc.cmp lt, %a, %b :(i32, i32) -> i1
+  return %c : i1
+}
+
+// CHECK-LABEL: func.func @expression_with_address_taken(
+// CHECK-SAME:      %[[VAL_0:.*]]: i32, %[[VAL_1:.*]]: i32, %[[VAL_2:.*]]: !emitc.ptr<i32>) -> i1 {
+// CHECK:         %[[VAL_3:.*]] = emitc.expression : i32 {
+// CHECK:           %[[VAL_4:.*]] = emitc.rem %[[VAL_0]], %[[VAL_1]] : (i32, i32) -> i32
+// CHECK:           emitc.yield %[[VAL_4]] : i32
+// CHECK:         }
+// CHECK:         %[[VAL_5:.*]] = emitc.expression : i1 {
+// CHECK:           %[[VAL_6:.*]] = emitc.apply "&"(%[[VAL_3]]) : (i32) -> !emitc.ptr<i32>
+// CHECK:           %[[VAL_7:.*]] = emitc.add %[[VAL_6]], %[[VAL_1]] : (!emitc.ptr<i32>, i32) -> !emitc.ptr<i32>
+// CHECK:           %[[VAL_8:.*]] = emitc.cmp lt, %[[VAL_7]], %[[VAL_2]] : (!emitc.ptr<i32>, !emitc.ptr<i32>) -> i1
+// CHECK:           emitc.yield %[[VAL_8]] : i1
+// CHECK:         }
+// CHECK:         return %[[VAL_5]] : i1
+// CHECK:       }
+
+func.func @expression_with_address_taken(%arg0: i32, %arg1: i32, %arg2: !emitc.ptr<i32>) -> i1 {
+  %a = emitc.rem %arg0, %arg1 : (i32, i32) -> (i32)
+  %b = emitc.apply "&"(%a) : (i32) -> !emitc.ptr<i32>
+  %c = emitc.add %b, %arg1 : (!emitc.ptr<i32>, i32) -> !emitc.ptr<i32>
+  %d = emitc.cmp lt, %c, %arg2 :(!emitc.ptr<i32>, !emitc.ptr<i32>) -> i1
+  return %d : i1
+}

diff  --git a/mlir/test/Target/Cpp/expressions.mlir b/mlir/test/Target/Cpp/expressions.mlir
new file mode 100644
index 00000000000000..9ec9dcc3c6a84b
--- /dev/null
+++ b/mlir/test/Target/Cpp/expressions.mlir
@@ -0,0 +1,212 @@
+// RUN: mlir-translate -mlir-to-cpp %s | FileCheck %s -check-prefix=CPP-DEFAULT
+// RUN: mlir-translate -mlir-to-cpp -declare-variables-at-top %s | FileCheck %s -check-prefix=CPP-DECLTOP
+
+// CPP-DEFAULT:      int32_t single_use(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]], int32_t [[VAL_4:v[0-9]+]]) {
+// CPP-DEFAULT-NEXT:   bool [[VAL_5:v[0-9]+]] = bar([[VAL_1]] * M_PI, [[VAL_3]]) - [[VAL_4]] < [[VAL_2]];
+// CPP-DEFAULT-NEXT:   int32_t [[VAL_6:v[0-9]+]];
+// CPP-DEFAULT-NEXT:   if ([[VAL_5]]) {
+// CPP-DEFAULT-NEXT:     [[VAL_6]] = [[VAL_1]];
+// CPP-DEFAULT-NEXT:   } else {
+// CPP-DEFAULT-NEXT:     [[VAL_6]] = [[VAL_1]];
+// CPP-DEFAULT-NEXT:   }
+// CPP-DEFAULT-NEXT:   return [[VAL_6]];
+// CPP-DEFAULT-NEXT: }
+
+// CPP-DECLTOP:      int32_t single_use(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]], int32_t [[VAL_4:v[0-9]+]]) {
+// CPP-DECLTOP-NEXT:   bool [[VAL_5:v[0-9]+]];
+// CPP-DECLTOP-NEXT:   int32_t [[VAL_6:v[0-9]+]];
+// CPP-DECLTOP-NEXT:   [[VAL_5]] = bar([[VAL_1]] * M_PI, [[VAL_3]]) - [[VAL_4]] < [[VAL_2]];
+// CPP-DECLTOP-NEXT:   ;
+// CPP-DECLTOP-NEXT:   if ([[VAL_5]]) {
+// CPP-DECLTOP-NEXT:     [[VAL_6]] = [[VAL_1]];
+// CPP-DECLTOP-NEXT:   } else {
+// CPP-DECLTOP-NEXT:     [[VAL_6]] = [[VAL_1]];
+// CPP-DECLTOP-NEXT:   }
+// CPP-DECLTOP-NEXT:   return [[VAL_6]];
+// CPP-DECLTOP-NEXT: }
+
+func.func @single_use(%arg0: i32, %arg1: i32, %arg2: i32, %arg3: i32) -> i32 {
+  %p0 = emitc.literal "M_PI" : i32
+  %e = emitc.expression : i1 {
+    %a = emitc.mul %arg0, %p0 : (i32, i32) -> i32
+    %b = emitc.call_opaque "bar" (%a, %arg2) : (i32, i32) -> (i32)
+    %c = emitc.sub %b, %arg3 : (i32, i32) -> i32
+    %d = emitc.cmp lt, %c, %arg1 :(i32, i32) -> i1
+    emitc.yield %d : i1
+  }
+  %v = "emitc.variable"(){value = #emitc.opaque<"">} : () -> i32
+  emitc.if %e {
+    emitc.assign %arg0 : i32 to %v : i32
+    emitc.yield
+  } else {
+    emitc.assign %arg0 : i32 to %v : i32
+    emitc.yield
+  }
+  return %v : i32
+}
+
+// CPP-DEFAULT: int32_t do_not_inline(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]]) {
+// CPP-DEFAULT-NEXT: int32_t [[VAL_4:v[0-9]+]] = ([[VAL_1]] + [[VAL_2]]) * [[VAL_3]];
+// CPP-DEFAULT-NEXT: return [[VAL_4]];
+// CPP-DEFAULT-NEXT:}
+
+// CPP-DECLTOP: int32_t do_not_inline(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]]) {
+// CPP-DECLTOP-NEXT: int32_t [[VAL_4:v[0-9]+]];
+// CPP-DECLTOP-NEXT: [[VAL_4]] = ([[VAL_1]] + [[VAL_2]]) * [[VAL_3]];
+// CPP-DECLTOP-NEXT: return [[VAL_4]];
+// CPP-DECLTOP-NEXT:}
+
+func.func @do_not_inline(%arg0: i32, %arg1: i32, %arg2 : i32) -> i32 {
+  %e = emitc.expression noinline : i32 {
+    %a = emitc.add %arg0, %arg1 : (i32, i32) -> i32
+    %b = emitc.mul %a, %arg2 : (i32, i32) -> i32
+    emitc.yield %b : i32
+  }
+  return %e : i32
+}
+
+// CPP-DEFAULT:      float paranthesis_for_low_precedence(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]]) {
+// CPP-DEFAULT-NEXT:   return (float) ([[VAL_1]] + [[VAL_2]] * [[VAL_3]]);
+// CPP-DEFAULT-NEXT: }
+
+// CPP-DECLTOP:      float paranthesis_for_low_precedence(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]]) {
+// CPP-DECLTOP-NEXT:   return (float) ([[VAL_1]] + [[VAL_2]] * [[VAL_3]]);
+// CPP-DECLTOP-NEXT: }
+
+func.func @paranthesis_for_low_precedence(%arg0: i32, %arg1: i32, %arg2: i32) -> f32 {
+  %e = emitc.expression : f32 {
+    %a = emitc.add %arg0, %arg1 : (i32, i32) -> i32
+    %b = emitc.mul %a, %arg2 : (i32, i32) -> i32
+    %d = emitc.cast %b : i32 to f32
+    emitc.yield %d : f32
+  }
+  return %e : f32
+}
+
+// CPP-DEFAULT:      int32_t multiple_uses(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]], int32_t [[VAL_4:v[0-9]+]]) {
+// CPP-DEFAULT-NEXT:   bool [[VAL_5:v[0-9]+]] = bar([[VAL_1]] * [[VAL_2]], [[VAL_3]]) - [[VAL_4]] < [[VAL_2]];
+// CPP-DEFAULT-NEXT:   int32_t [[VAL_6:v[0-9]+]];
+// CPP-DEFAULT-NEXT:   if ([[VAL_5]]) {
+// CPP-DEFAULT-NEXT:     [[VAL_6]] = [[VAL_1]];
+// CPP-DEFAULT-NEXT:   } else {
+// CPP-DEFAULT-NEXT:     [[VAL_6]] = [[VAL_1]];
+// CPP-DEFAULT-NEXT:   }
+// CPP-DEFAULT-NEXT:   bool [[VAL_7:v[0-9]+]];
+// CPP-DEFAULT-NEXT:   [[VAL_7]] = [[VAL_5]];
+// CPP-DEFAULT-NEXT:   return [[VAL_6]];
+// CPP-DEFAULT-NEXT: }
+
+// CPP-DECLTOP:      int32_t multiple_uses(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]], int32_t [[VAL_4:v[0-9]+]]) {
+// CPP-DECLTOP-NEXT:   bool [[VAL_5:v[0-9]+]];
+// CPP-DECLTOP-NEXT:   int32_t [[VAL_6:v[0-9]+]];
+// CPP-DECLTOP-NEXT:   bool [[VAL_7:v[0-9]+]];
+// CPP-DECLTOP-NEXT:   [[VAL_5]] = bar([[VAL_1]] * [[VAL_2]], [[VAL_3]]) - [[VAL_4]] < [[VAL_2]];
+// CPP-DECLTOP-NEXT:   ;
+// CPP-DECLTOP-NEXT:   if ([[VAL_5]]) {
+// CPP-DECLTOP-NEXT:     [[VAL_6]] = [[VAL_1]];
+// CPP-DECLTOP-NEXT:   } else {
+// CPP-DECLTOP-NEXT:     [[VAL_6]] = [[VAL_1]];
+// CPP-DECLTOP-NEXT:   }
+// CPP-DECLTOP-NEXT:   ;
+// CPP-DECLTOP-NEXT:   [[VAL_7]] = [[VAL_5]];
+// CPP-DECLTOP-NEXT:   return [[VAL_6]];
+// CPP-DECLTOP-NEXT: }
+
+func.func @multiple_uses(%arg0: i32, %arg1: i32, %arg2: i32, %arg3: i32) -> i32 {
+  %e = emitc.expression : i1 {
+    %a = emitc.mul %arg0, %arg1 : (i32, i32) -> i32
+    %b = emitc.call_opaque "bar" (%a, %arg2) : (i32, i32) -> (i32)
+    %c = emitc.sub %b, %arg3 : (i32, i32) -> i32
+    %d = emitc.cmp lt, %c, %arg1 :(i32, i32) -> i1
+    emitc.yield %d : i1
+  }
+  %v = "emitc.variable"(){value = #emitc.opaque<"">} : () -> i32
+  emitc.if %e {
+    emitc.assign %arg0 : i32 to %v : i32
+    emitc.yield
+  } else {
+    emitc.assign %arg0 : i32 to %v : i32
+    emitc.yield
+  }
+  %q = "emitc.variable"(){value = #emitc.opaque<"">} : () -> i1
+  emitc.assign %e : i1 to %q : i1
+  return %v : i32
+}
+
+// CPP-DEFAULT:      int32_t 
diff erent_expressions(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]], int32_t [[VAL_4:v[0-9]+]]) {
+// CPP-DEFAULT-NEXT:   int32_t [[VAL_5:v[0-9]+]] = [[VAL_3]] % [[VAL_4]];
+// CPP-DEFAULT-NEXT:   int32_t [[VAL_6:v[0-9]+]] = bar([[VAL_5]], [[VAL_1]] * [[VAL_2]]);
+// CPP-DEFAULT-NEXT:   int32_t [[VAL_7:v[0-9]+]];
+// CPP-DEFAULT-NEXT:   if ([[VAL_6]] - [[VAL_4]] < [[VAL_2]]) {
+// CPP-DEFAULT-NEXT:     [[VAL_7]] = [[VAL_1]];
+// CPP-DEFAULT-NEXT:   } else {
+// CPP-DEFAULT-NEXT:     [[VAL_7]] = [[VAL_1]];
+// CPP-DEFAULT-NEXT:   }
+// CPP-DEFAULT-NEXT:   return [[VAL_7]];
+// CPP-DEFAULT-NEXT: }
+
+// CPP-DECLTOP:      int32_t 
diff erent_expressions(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t [[VAL_3:v[0-9]+]], int32_t [[VAL_4:v[0-9]+]]) {
+// CPP-DECLTOP-NEXT:   int32_t [[VAL_5:v[0-9]+]];
+// CPP-DECLTOP-NEXT:   int32_t [[VAL_6:v[0-9]+]];
+// CPP-DECLTOP-NEXT:   int32_t [[VAL_7:v[0-9]+]];
+// CPP-DECLTOP-NEXT:   [[VAL_5]] = [[VAL_3]] % [[VAL_4]];
+// CPP-DECLTOP-NEXT:   [[VAL_6]] = bar([[VAL_5]], [[VAL_1]] * [[VAL_2]]);
+// CPP-DECLTOP-NEXT:   ;
+// CPP-DECLTOP-NEXT:   if ([[VAL_6]] - [[VAL_4]] < [[VAL_2]]) {
+// CPP-DECLTOP-NEXT:     [[VAL_7]] = [[VAL_1]];
+// CPP-DECLTOP-NEXT:   } else {
+// CPP-DECLTOP-NEXT:     [[VAL_7]] = [[VAL_1]];
+// CPP-DECLTOP-NEXT:   }
+// CPP-DECLTOP-NEXT:   return [[VAL_7]];
+// CPP-DECLTOP-NEXT: }
+
+func.func @
diff erent_expressions(%arg0: i32, %arg1: i32, %arg2: i32, %arg3: i32) -> i32 {
+  %e1 = emitc.expression : i32 {
+    %a = emitc.rem %arg2, %arg3 : (i32, i32) -> i32
+    emitc.yield %a : i32
+  }
+  %e2 = emitc.expression : i32 {
+    %a = emitc.mul %arg0, %arg1 : (i32, i32) -> i32
+    %b = emitc.call_opaque "bar" (%e1, %a) : (i32, i32) -> (i32)
+    emitc.yield %b : i32
+  }
+  %e3 = emitc.expression : i1 {
+    %c = emitc.sub %e2, %arg3 : (i32, i32) -> i32
+    %d = emitc.cmp lt, %c, %arg1 :(i32, i32) -> i1
+    emitc.yield %d : i1
+  }
+  %v = "emitc.variable"(){value = #emitc.opaque<"">} : () -> i32
+  emitc.if %e3 {
+    emitc.assign %arg0 : i32 to %v : i32
+    emitc.yield
+  } else {
+    emitc.assign %arg0 : i32 to %v : i32
+    emitc.yield
+  }
+  return %v : i32
+}
+
+// CPP-DEFAULT:      bool expression_with_address_taken(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t* [[VAL_3]]) {
+// CPP-DEFAULT-NEXT:   int32_t [[VAL_4:v[0-9]+]] = [[VAL_1]] % [[VAL_2]];
+// CPP-DEFAULT-NEXT:   return &[[VAL_4]] - [[VAL_2]] < [[VAL_3]];
+// CPP-DEFAULT-NEXT: }
+
+// CPP-DECLTOP:      bool expression_with_address_taken(int32_t [[VAL_1:v[0-9]+]], int32_t [[VAL_2:v[0-9]+]], int32_t* [[VAL_3]]) {
+// CPP-DECLTOP-NEXT:   int32_t [[VAL_4:v[0-9]+]];
+// CPP-DECLTOP-NEXT:   [[VAL_4]] = [[VAL_1]] % [[VAL_2]];
+// CPP-DECLTOP-NEXT:   return &[[VAL_4]] - [[VAL_2]] < [[VAL_3]];
+// CPP-DECLTOP-NEXT: }
+
+func.func @expression_with_address_taken(%arg0: i32, %arg1: i32, %arg2: !emitc.ptr<i32>) -> i1 {
+  %a = emitc.expression : i32 {
+    %b = emitc.rem %arg0, %arg1 : (i32, i32) -> i32
+    emitc.yield %b : i32
+  }
+  %c = emitc.expression : i1 {
+    %d = emitc.apply "&"(%a) : (i32) -> !emitc.ptr<i32>
+    %e = emitc.sub %d, %arg1 : (!emitc.ptr<i32>, i32) -> !emitc.ptr<i32>
+    %f = emitc.cmp lt, %e, %arg2 : (!emitc.ptr<i32>, !emitc.ptr<i32>) -> i1
+    emitc.yield %f : i1
+  }
+  return %c : i1
+}

diff  --git a/mlir/test/Target/Cpp/for.mlir b/mlir/test/Target/Cpp/for.mlir
index 90504b1347bb46..b9bd3d98465a23 100644
--- a/mlir/test/Target/Cpp/for.mlir
+++ b/mlir/test/Target/Cpp/for.mlir
@@ -2,20 +2,32 @@
 // RUN: mlir-translate -mlir-to-cpp -declare-variables-at-top %s | FileCheck %s -check-prefix=CPP-DECLTOP
 
 func.func @test_for(%arg0 : index, %arg1 : index, %arg2 : index) {
-  emitc.for %i0 = %arg0 to %arg1 step %arg2 {
+  %lb = emitc.expression : index {
+    %a = emitc.add %arg0, %arg1 : (index, index) -> index
+    emitc.yield %a : index
+  }
+  %ub = emitc.expression : index {
+    %a = emitc.mul %arg1, %arg2 : (index, index) -> index
+    emitc.yield %a : index
+  }
+  %step = emitc.expression : index {
+    %a = emitc.div %arg0, %arg2 : (index, index) -> index
+    emitc.yield %a : index
+  }
+  emitc.for %i0 = %lb to %ub step %step {
     %0 = emitc.call_opaque "f"() : () -> i32
   }
   return
 }
-// CPP-DEFAULT: void test_for(size_t [[START:[^ ]*]], size_t [[STOP:[^ ]*]], size_t [[STEP:[^ ]*]]) {
-// CPP-DEFAULT-NEXT: for (size_t [[ITER:[^ ]*]] = [[START]]; [[ITER]] < [[STOP]]; [[ITER]] += [[STEP]]) {
+// CPP-DEFAULT: void test_for(size_t [[V1:[^ ]*]], size_t [[V2:[^ ]*]], size_t [[V3:[^ ]*]]) {
+// CPP-DEFAULT-NEXT: for (size_t [[ITER:[^ ]*]] = [[V1]] + [[V2]]; [[ITER]] < ([[V2]] * [[V3]]); [[ITER]] += [[V1]] / [[V3]]) {
 // CPP-DEFAULT-NEXT: int32_t [[V4:[^ ]*]] = f();
 // CPP-DEFAULT-NEXT: }
 // CPP-DEFAULT-NEXT: return;
 
-// CPP-DECLTOP: void test_for(size_t [[START:[^ ]*]], size_t [[STOP:[^ ]*]], size_t [[STEP:[^ ]*]]) {
+// CPP-DECLTOP: void test_for(size_t [[V1:[^ ]*]], size_t [[V2:[^ ]*]], size_t [[V3:[^ ]*]]) {
 // CPP-DECLTOP-NEXT: int32_t [[V4:[^ ]*]];
-// CPP-DECLTOP-NEXT: for (size_t [[ITER:[^ ]*]] = [[START]]; [[ITER]] < [[STOP]]; [[ITER]] += [[STEP]]) {
+// CPP-DECLTOP-NEXT: for (size_t [[ITER:[^ ]*]] = [[V1]] + [[V2]]; [[ITER]] < ([[V2]] * [[V3]]); [[ITER]] += [[V1]] / [[V3]]) {
 // CPP-DECLTOP-NEXT: [[V4]] = f();
 // CPP-DECLTOP-NEXT: }
 // CPP-DECLTOP-NEXT: return;