Refactor OSLogOptimization utility functions into a separate file

Author: Josh Learn

include/swift/SILOptimizer/Utils/CompileTimeInterpolationUtils.h

@@ -0,0 +1,46 @@
+//===--- CompileTimeInterpolationUtils.h ----------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2021 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+// Utilities for the compile-time string interpolation approach used by the
+// OSLogOptimization pass.
+
+#ifndef SWIFT_SILOPTIMIZER_COMPILE_TIME_INTERPOLATION_H
+#define SWIFT_SILOPTIMIZER_COMPILE_TIME_INTERPOLATION_H
+
+#include "swift/SIL/SILBasicBlock.h"
+#include "swift/SIL/SILConstants.h"
+#include "swift/SILOptimizer/Utils/ConstExpr.h"
+
+namespace swift {
+
+/// Decide if the given instruction (which could possibly be a call) should
+/// be constant evaluated.
+///
+/// \returns true iff the given instruction is not a call or if it is, it calls
+/// a known constant-evaluable function such as string append etc., or calls
+/// a function annotate as "constant_evaluable".
+bool shouldAttemptEvaluation(SILInstruction *inst);
+
+/// Skip or evaluate the given instruction based on the evaluation policy and
+/// handle errors. The policy is to evaluate all non-apply instructions as well
+/// as apply instructions that are marked as "constant_evaluable".
+std::pair<Optional<SILBasicBlock::iterator>, Optional<SymbolicValue>>
+evaluateOrSkip(ConstExprStepEvaluator &stepEval, SILBasicBlock::iterator instI);
+
+/// Given a vector of SILValues \p worklist, compute the set of transitive
+/// users of these values (excluding the worklist values) by following the
+/// use-def chain starting at value. Note that this function does not follow
+/// use-def chains though branches.
+void getTransitiveUsers(SILInstructionResultArray values,
+                        SmallVectorImpl<SILInstruction *> &users);
+} // end namespace swift
+#endif

lib/SILOptimizer/Mandatory/OSLogOptimization.cpp

@@ -76,11 +76,12 @@
 #include "swift/AST/DiagnosticsSIL.h"
 #include "swift/AST/Expr.h"
 #include "swift/AST/Module.h"
+#include "swift/AST/SemanticAttrs.h"
 #include "swift/AST/SubstitutionMap.h"
 #include "swift/Basic/OptimizationMode.h"
-#include "swift/AST/SemanticAttrs.h"
 #include "swift/Demangling/Demangle.h"
 #include "swift/Demangling/Demangler.h"
+#include "swift/SIL/BasicBlockBits.h"
 #include "swift/SIL/BasicBlockUtils.h"
 #include "swift/SIL/CFG.h"
 #include "swift/SIL/InstructionUtils.h"
@@ -93,10 +94,10 @@
 #include "swift/SIL/SILLocation.h"
 #include "swift/SIL/SILModule.h"
 #include "swift/SIL/TypeLowering.h"
-#include "swift/SIL/BasicBlockBits.h"
 #include "swift/SILOptimizer/PassManager/Passes.h"
 #include "swift/SILOptimizer/PassManager/Transforms.h"
 #include "swift/SILOptimizer/Utils/CFGOptUtils.h"
+#include "swift/SILOptimizer/Utils/CompileTimeInterpolationUtils.h"
 #include "swift/SILOptimizer/Utils/ConstExpr.h"
 #include "swift/SILOptimizer/Utils/InstructionDeleter.h"
 #include "swift/SILOptimizer/Utils/SILInliner.h"
@@ -245,38 +246,6 @@ static bool isIntegerOrBoolType(SILType silType, ASTContext &astContext) {
   return nominalDecl && isStdlibIntegerOrBoolDecl(nominalDecl, astContext);
 }
 
-/// Decide if the given instruction (which could possibly be a call) should
-/// be constant evaluated.
-///
-/// \returns true iff the given instruction is not a call or if it is, it calls
-/// a known constant-evaluable function such as string append etc., or calls
-/// a function annotate as "constant_evaluable".
-static bool shouldAttemptEvaluation(SILInstruction *inst) {
-  auto *apply = dyn_cast<ApplyInst>(inst);
-  if (!apply)
-    return true;
-  SILFunction *calleeFun = apply->getCalleeFunction();
-  if (!calleeFun)
-    return false;
-  return isConstantEvaluable(calleeFun);
-}
-
-/// Skip or evaluate the given instruction based on the evaluation policy and
-/// handle errors. The policy is to evaluate all non-apply instructions as well
-/// as apply instructions that are marked as "constant_evaluable".
-static std::pair<Optional<SILBasicBlock::iterator>, Optional<SymbolicValue>>
-evaluateOrSkip(ConstExprStepEvaluator &stepEval,
-               SILBasicBlock::iterator instI) {
-  SILInstruction *inst = &(*instI);
-
-  // Note that skipping a call conservatively approximates its effects on the
-  // interpreter state.
-  if (shouldAttemptEvaluation(inst)) {
-    return stepEval.tryEvaluateOrElseMakeEffectsNonConstant(instI);
-  }
-  return stepEval.skipByMakingEffectsNonConstant(instI);
-}
-
 /// Return true iff the given value is a stdlib Int or Bool and it not a direct
 /// construction of Int or Bool.
 static bool isFoldableIntOrBool(SILValue value, ASTContext &astContext) {
@@ -818,31 +787,6 @@ static SILValue emitCodeForSymbolicValue(SymbolicValue symVal,
   }
 }
 
-/// Given a SILValue \p value, compute the set of transitive users of the value
-/// (excluding value itself) by following the use-def chain starting at value.
-/// Note that this function does not follow use-def chains though branches.
-static void getTransitiveUsers(SILValue value,
-                               SmallVectorImpl<SILInstruction *> &users) {
-  // Collect the instructions that are data dependent on the value using a
-  // fix point iteration.
-  SmallPtrSet<SILInstruction *, 16> visitedUsers;
-  SmallVector<SILValue, 16> worklist;
-  worklist.push_back(value);
-
-  while (!worklist.empty()) {
-    SILValue currVal = worklist.pop_back_val();
-    for (Operand *use : currVal->getUses()) {
-      SILInstruction *user = use->getUser();
-      if (visitedUsers.count(user))
-        continue;
-      visitedUsers.insert(user);
-      llvm::copy(user->getResults(), std::back_inserter(worklist));
-    }
-  }
-  // At this point, visitedUsers have all the transitive, data-dependent uses.
-  users.append(visitedUsers.begin(), visitedUsers.end());
-}
-
 /// Collect the end points of the instructions that are data dependent on \c
 /// value. A instruction is data dependent on \c value if its result may
 /// transitively depends on \c value. Note that data dependencies through
@@ -853,7 +797,7 @@ static void getTransitiveUsers(SILValue value,
 /// \param endUsers buffer for storing the found end points of the data
 /// dependence chain.
 static void
-getEndPointsOfDataDependentChain(SILValue value, SILFunction *fun,
+getEndPointsOfDataDependentChain(SingleValueInstruction *value, SILFunction *fun,
                                  SmallVectorImpl<SILInstruction *> &endUsers) {
   assert(!value->getType().isAddress());
 

lib/SILOptimizer/Utils/CMakeLists.txt

@@ -6,6 +6,7 @@ target_sources(swiftSILOptimizer PRIVATE
   CanonicalizeBorrowScope.cpp
   CastOptimizer.cpp
   CheckedCastBrJumpThreading.cpp
+  CompileTimeInterpolationUtils.cpp
   ConstantFolding.cpp
   ConstExpr.cpp
   Devirtualize.cpp

lib/SILOptimizer/Utils/CompileTimeInterpolationUtils.cpp

@@ -0,0 +1,60 @@
+//===--- CompileTimeInterpolationUtils.cpp -------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2021 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#include "swift/SILOptimizer/Utils/CompileTimeInterpolationUtils.h"
+#include "swift/AST/ASTContext.h"
+#include "swift/SIL/SILFunction.h"
+
+using namespace swift;
+
+bool swift::shouldAttemptEvaluation(SILInstruction *inst) {
+  auto *apply = dyn_cast<ApplyInst>(inst);
+  if (!apply)
+    return true;
+  SILFunction *calleeFun = apply->getCalleeFunction();
+  if (!calleeFun)
+    return false;
+  return isConstantEvaluable(calleeFun);
+}
+
+std::pair<Optional<SILBasicBlock::iterator>, Optional<SymbolicValue>>
+swift::evaluateOrSkip(ConstExprStepEvaluator &stepEval,
+                      SILBasicBlock::iterator instI) {
+  SILInstruction *inst = &(*instI);
+
+  // Note that skipping a call conservatively approximates its effects on the
+  // interpreter state.
+  if (shouldAttemptEvaluation(inst)) {
+    return stepEval.tryEvaluateOrElseMakeEffectsNonConstant(instI);
+  }
+  return stepEval.skipByMakingEffectsNonConstant(instI);
+}
+
+void swift::getTransitiveUsers(SILInstructionResultArray values,
+                               SmallVectorImpl<SILInstruction *> &users) {
+  // Collect the instructions that are data dependent on the value using a
+  // fix point iteration.
+  SmallPtrSet<SILInstruction *, 16> visited;
+  SmallVector<SILValue, 16> worklist;
+  llvm::copy(values, std::back_inserter(worklist));
+  while (!worklist.empty()) {
+    SILValue currVal = worklist.pop_back_val();
+    for (Operand *use : currVal->getUses()) {
+      SILInstruction *user = use->getUser();
+      if (visited.count(user))
+        continue;
+      visited.insert(user);
+      llvm::copy(user->getResults(), std::back_inserter(worklist));
+    }
+  }
+  users.append(visited.begin(), visited.end());
+}