JIT: Forward sub candidate-set multi-statement lookahead

src/coreclr/jit/compiler.h

@@ -72,22 +72,23 @@ inline var_types genActualType(T value);
  *                  Forward declarations
  */
 
-struct InfoHdr;            // defined in GCInfo.h
-struct escapeMapping_t;    // defined in fgdiagnostic.cpp
-class emitter;             // defined in emit.h
-struct ShadowParamVarInfo; // defined in GSChecks.cpp
-struct InitVarDscInfo;     // defined in registerargconvention.h
-class FgStack;             // defined in fgbasic.cpp
-class Instrumentor;        // defined in fgprofile.cpp
-class SpanningTreeVisitor; // defined in fgprofile.cpp
-class CSE_DataFlow;        // defined in optcse.cpp
-struct CSEdsc;             // defined in optcse.h
-class CSE_HeuristicCommon; // defined in optcse.h
-class OptBoolsDsc;         // defined in optimizer.cpp
-struct JumpThreadInfo;     // defined in redundantbranchopts.cpp
-class ProfileSynthesis;    // defined in profilesynthesis.h
-class PerLoopInfo;         // defined in inductionvariableopts.cpp
-class RangeCheck;          // defined in rangecheck.h
+struct InfoHdr;             // defined in GCInfo.h
+struct escapeMapping_t;     // defined in fgdiagnostic.cpp
+class emitter;              // defined in emit.h
+struct ShadowParamVarInfo;  // defined in GSChecks.cpp
+struct InitVarDscInfo;      // defined in registerargconvention.h
+class FgStack;              // defined in fgbasic.cpp
+class Instrumentor;         // defined in fgprofile.cpp
+class SpanningTreeVisitor;  // defined in fgprofile.cpp
+class CSE_DataFlow;         // defined in optcse.cpp
+struct CSEdsc;              // defined in optcse.h
+class CSE_HeuristicCommon;  // defined in optcse.h
+class OptBoolsDsc;          // defined in optimizer.cpp
+struct JumpThreadInfo;      // defined in redundantbranchopts.cpp
+struct ForwardSubCandidate; // defined in forwardsub.cpp
+class ProfileSynthesis;     // defined in profilesynthesis.h
+class PerLoopInfo;          // defined in inductionvariableopts.cpp
+class RangeCheck;           // defined in rangecheck.h
 #ifdef TARGET_WASM
 class WasmInterval; // defined in fgwasm.h
 #endif
@@ -6847,7 +6848,11 @@ class Compiler
 
     PhaseStatus fgForwardSub();
     bool fgForwardSubBlock(BasicBlock* block);
-    bool fgForwardSubStatement(Statement* statement);
+    bool fgForwardSubIsDefCandidate(Statement* stmt, GenTree** fwdSubNode, unsigned* lclNum);
+    static bool fgForwardSubCanReorderPast(ForwardSubCandidate* candidate, GenTreeFlags stmtFlags);
+    bool fgForwardSubHasStoreInterferenceWithCandidate(ForwardSubCandidate* candidate, Statement* stmt);
+    bool fgForwardSubStatement(ForwardSubCandidate* candidate, Statement* useStmt);
+    bool fgForwardSubStatement(Statement* stmt);
     bool fgForwardSubHasStoreInterference(Statement* defStmt, Statement* nextStmt, GenTree* nextStmtUse);
     void fgForwardSubUpdateLiveness(GenTree* newSubListFirst, GenTree* newSubListLast);