Refactor LateLowerGCFrame. We do not need inheritance.

src/llvm-gc-interface-passes.h

@@ -326,8 +326,7 @@ struct LateLowerGCFrame:  private JuliaPassContext {
     LateLowerGCFrame(function_ref<DominatorTree &()> GetDT) : GetDT(GetDT) {}
 
 public:
-    int need_gc_preserve_hook;
-    virtual bool runOnFunction(Function &F, bool *CFGModified = nullptr);
+    bool runOnFunction(Function &F, bool *CFGModified = nullptr);
 
 private:
     CallInst *pgcstack;
@@ -362,6 +361,7 @@ struct LateLowerGCFrame:  private JuliaPassContext {
     void PlaceGCFrameStores(State &S, unsigned MinColorRoot, ArrayRef<int> Colors, Value *GCFrame);
     void PlaceRootsAndUpdateCalls(SmallVectorImpl<int> &Colors, State &S, std::map<Value *, std::pair<int, int>>);
     void CleanupWriteBarriers(Function &F, State *S, const SmallVector<CallInst*, 0> &WriteBarriers, bool *CFGModified);
+    void cleanupGCPreserve(Function &F, CallInst *CI, Value *callee, Type *T_size);
     bool CleanupIR(Function &F, State *S, bool *CFGModified);
     void NoteUseChain(State &S, BBState &BBS, User *TheUser);
     SmallVector<int, 1> GetPHIRefinements(PHINode *phi, State &S);
@@ -374,11 +374,6 @@ struct LateLowerGCFrame:  private JuliaPassContext {
 #endif
 };
 
-struct LateLowerGCFrameCustom: public LateLowerGCFrame {
-public:
-    bool runOnFunction(Function &F, bool *CFGModified = nullptr) override;
-};
-
 // The final GC lowering pass. This pass lowers platform-agnostic GC
 // intrinsics to platform-dependent instruction sequences. The
 // intrinsics it targets are those produced by the late GC frame
@@ -434,4 +429,12 @@ struct FinalLowerGC: private JuliaPassContext {
 #endif
 };
 
+inline bool isSpecialPtr(Type *Ty) {
+    PointerType *PTy = dyn_cast<PointerType>(Ty);
+    if (!PTy)
+        return false;
+    unsigned AS = PTy->getAddressSpace();
+    return AddressSpace::FirstSpecial <= AS && AS <= AddressSpace::LastSpecial;
+}
+
 #endif // LLVM_GC_PASSES_H

src/llvm-julia-passes.inc

@@ -11,7 +11,7 @@ MODULE_PASS("LowerPTLSPass", LowerPTLSPass, LowerPTLSPass())
 //Function passes
 #ifdef FUNCTION_PASS
 FUNCTION_PASS("DemoteFloat16", DemoteFloat16Pass, DemoteFloat16Pass())
-FUNCTION_PASS("LateLowerGCFrameCustom", LateLowerGCPass, LateLowerGCPass())
+FUNCTION_PASS("LateLowerGCFrame", LateLowerGCPass, LateLowerGCPass())
 FUNCTION_PASS("AllocOpt", AllocOptPass, AllocOptPass())
 FUNCTION_PASS("PropagateJuliaAddrspaces", PropagateJuliaAddrspacesPass, PropagateJuliaAddrspacesPass())
 FUNCTION_PASS("LowerExcHandlers", LowerExcHandlersPass, LowerExcHandlersPass())

src/llvm-late-gc-lowering-mmtk.cpp

@@ -1,6 +1,47 @@
 #include "llvm-gc-interface-passes.h"
 
-bool LateLowerGCFrameCustom::runOnFunction(Function &F, bool *CFGModified) {
-    need_gc_preserve_hook = 1;
-    return LateLowerGCFrame::runOnFunction(F, CFGModified);
+void LateLowerGCFrame::cleanupGCPreserve(Function &F, CallInst *CI, Value *callee, Type *T_size) {
+    if (callee == gc_preserve_begin_func) {
+        // Initialize an IR builder.
+        IRBuilder<> builder(CI);
+
+        builder.SetCurrentDebugLocation(CI->getDebugLoc());
+        size_t nargs = 0;
+        State S2(F);
+
+        std::vector<Value*> args;
+        for (Use &U : CI->args()) {
+            Value *V = U;
+            if (isa<Constant>(V))
+                continue;
+            if (isa<PointerType>(V->getType())) {
+                if (isSpecialPtr(V->getType())) {
+                    int Num = Number(S2, V);
+                    if (Num >= 0) {
+                        nargs++;
+                        Value *Val = GetPtrForNumber(S2, Num, CI);
+                        args.push_back(Val);
+                    }
+                }
+            } else {
+                auto Nums = NumberAll(S2, V);
+                for (int Num : Nums) {
+                    if (Num < 0)
+                        continue;
+                    Value *Val = GetPtrForNumber(S2, Num, CI);
+                    args.push_back(Val);
+                    nargs++;
+                }
+            }
+        }
+        args.insert(args.begin(), ConstantInt::get(T_size, nargs));
+
+        ArrayRef<Value*> args_llvm = ArrayRef<Value*>(args);
+        builder.CreateCall(getOrDeclare(jl_well_known::GCPreserveBeginHook), args_llvm );
+    } else if (callee == gc_preserve_end_func) {
+        // Initialize an IR builder.
+        IRBuilder<> builder(CI);
+        builder.SetCurrentDebugLocation(CI->getDebugLoc());
+        builder.CreateCall(getOrDeclare(jl_well_known::GCPreserveEndHook), {});
+    }
 }

src/llvm-late-gc-lowering-stock.cpp

@@ -1,6 +1,5 @@
 #include "llvm-gc-interface-passes.h"
 
-bool LateLowerGCFrameCustom::runOnFunction(Function &F, bool *CFGModified) {
-    need_gc_preserve_hook = 0;
-    return LateLowerGCFrame::runOnFunction(F, CFGModified);
+void LateLowerGCFrame::cleanupGCPreserve(Function &F, CallInst *CI, Value *callee, Type *T_size) {
+    // Do nothing for the stock GC
 }

src/llvm-late-gc-lowering.cpp

@@ -13,14 +13,6 @@ static bool isTrackedValue(Value *V) {
     return PT && PT->getAddressSpace() == AddressSpace::Tracked;
 }
 
-static bool isSpecialPtr(Type *Ty) {
-    PointerType *PTy = dyn_cast<PointerType>(Ty);
-    if (!PTy)
-        return false;
-    unsigned AS = PTy->getAddressSpace();
-    return AddressSpace::FirstSpecial <= AS && AS <= AddressSpace::LastSpecial;
-}
-
 // return how many Special pointers are in T (count > 0),
 // and if there is anything else in T (all == false)
 CountTrackedPointers::CountTrackedPointers(Type *T, bool ignore_loaded) {
@@ -2089,55 +2081,11 @@ bool LateLowerGCFrame::CleanupIR(Function &F, State *S, bool *CFGModified) {
                 continue;
             }
             Value *callee = CI->getCalledOperand();
-            if (callee && (callee == gc_flush_func || callee == gc_preserve_begin_func
+            if (callee && callee == gc_flush_func) {
+                /* No replacement */
+            } else if (callee && (callee == gc_preserve_begin_func
                         || callee == gc_preserve_end_func)) {
-                /* Replace with a call to the hook functions */
-                if (need_gc_preserve_hook) {
-                    if (callee == gc_preserve_begin_func) {
-                        // Initialize an IR builder.
-                        IRBuilder<> builder(CI);
-
-                        builder.SetCurrentDebugLocation(CI->getDebugLoc());
-                        size_t nargs = 0;
-                        State S2(F);
-
-                        std::vector<Value*> args;
-                        for (Use &U : CI->args()) {
-                            Value *V = U;
-                            if (isa<Constant>(V))
-                                continue;
-                            if (isa<PointerType>(V->getType())) {
-                                if (isSpecialPtr(V->getType())) {
-                                    int Num = Number(S2, V);
-                                    if (Num >= 0) {
-                                        nargs++;
-                                        Value *Val = GetPtrForNumber(S2, Num, CI);
-                                        args.push_back(Val);
-                                    }
-                                }
-                            } else {
-                                auto Nums = NumberAll(S2, V);
-                                for (int Num : Nums) {
-                                    if (Num < 0)
-                                        continue;
-                                    Value *Val = GetPtrForNumber(S2, Num, CI);
-                                    args.push_back(Val);
-                                    nargs++;
-                                }
-                            }
-                        }
-                        args.insert(args.begin(), ConstantInt::get(T_size, nargs));
-
-                        ArrayRef<Value*> args_llvm = ArrayRef<Value*>(args);
-                        builder.CreateCall(getOrDeclare(jl_well_known::GCPreserveBeginHook), args_llvm );
-                    } else if (callee == gc_preserve_end_func) {
-                        // Initialize an IR builder.
-                        IRBuilder<> builder(CI);
-                        builder.SetCurrentDebugLocation(CI->getDebugLoc());
-                        builder.CreateCall(getOrDeclare(jl_well_known::GCPreserveEndHook), {});
-                    }
-                }
-                // Otherwise no replacement
+                cleanupGCPreserve(F, CI, callee, T_size);
             } else if (pointer_from_objref_func != nullptr && callee == pointer_from_objref_func) {
                 auto *obj = CI->getOperand(0);
                 auto *ASCI = new AddrSpaceCastInst(obj, CI->getType(), "", CI);