Duplicates Tracket accounts for possible changes in Constant usage after optimization

Author: VyacheslavLevytskyy

llvm/lib/Target/SPIRV/SPIRVDuplicatesTracker.cpp

@@ -12,37 +12,39 @@
 //===----------------------------------------------------------------------===//
 
 #include "SPIRVDuplicatesTracker.h"
+#include "SPIRVInstrInfo.h"
 
 #define DEBUG_TYPE "build-dep-graph"
 
 using namespace llvm;
 
 template <typename T>
 void SPIRVGeneralDuplicatesTracker::prebuildReg2Entry(
-    SPIRVDuplicatesTracker<T> &DT, SPIRVReg2EntryTy &Reg2Entry) {
+    SPIRVDuplicatesTracker<T> &DT, SPIRVReg2EntryTy &Reg2Entry,
+    const SPIRVInstrInfo *TII) {
   for (auto &TPair : DT.getAllUses()) {
     for (auto &RegPair : TPair.second) {
       const MachineFunction *MF = RegPair.first;
       Register R = RegPair.second;
       MachineInstr *MI = MF->getRegInfo().getUniqueVRegDef(R);
-      if (!MI)
+      if (!MI || (TPair.second.getIsConst() && !TII->isConstantInstr(*MI)))
         continue;
       Reg2Entry[&MI->getOperand(0)] = &TPair.second;
     }
   }
 }
 
 void SPIRVGeneralDuplicatesTracker::buildDepsGraph(
-    std::vector<SPIRV::DTSortableEntry *> &Graph,
+    std::vector<SPIRV::DTSortableEntry *> &Graph, const SPIRVInstrInfo *TII,
     MachineModuleInfo *MMI = nullptr) {
   SPIRVReg2EntryTy Reg2Entry;
-  prebuildReg2Entry(TT, Reg2Entry);
-  prebuildReg2Entry(CT, Reg2Entry);
-  prebuildReg2Entry(GT, Reg2Entry);
-  prebuildReg2Entry(FT, Reg2Entry);
-  prebuildReg2Entry(AT, Reg2Entry);
-  prebuildReg2Entry(MT, Reg2Entry);
-  prebuildReg2Entry(ST, Reg2Entry);
+  prebuildReg2Entry(TT, Reg2Entry, TII);
+  prebuildReg2Entry(CT, Reg2Entry, TII);
+  prebuildReg2Entry(GT, Reg2Entry, TII);
+  prebuildReg2Entry(FT, Reg2Entry, TII);
+  prebuildReg2Entry(AT, Reg2Entry, TII);
+  prebuildReg2Entry(MT, Reg2Entry, TII);
+  prebuildReg2Entry(ST, Reg2Entry, TII);
 
   for (auto &Op2E : Reg2Entry) {
     SPIRV::DTSortableEntry *E = Op2E.second;
@@ -65,20 +67,19 @@ void SPIRVGeneralDuplicatesTracker::buildDepsGraph(
         if (MI->getOpcode() == SPIRV::OpConstantFunctionPointerINTEL && i == 2)
           continue;
         MachineOperand *RegOp = &VRegDef->getOperand(0);
-        LLVM_DEBUG({
-          if (Reg2Entry.count(RegOp) == 0 &&
-              (MI->getOpcode() != SPIRV::OpVariable || i != 3)) {
-            dbgs() << "Unexpected pattern while building a dependency "
-                      "graph.\nInstruction: ";
-            MI->print(dbgs());
-            dbgs() << "Operand: ";
-            Op.print(dbgs());
-            dbgs() << "\nOperand definition: ";
-            VRegDef->print(dbgs());
-          }
-        });
-        assert((MI->getOpcode() == SPIRV::OpVariable && i == 3) ||
-               Reg2Entry.count(RegOp));
+        if (Reg2Entry.count(RegOp) == 0 &&
+            (MI->getOpcode() != SPIRV::OpVariable || i != 3)) {
+          std::string DiagMsg;
+          raw_string_ostream OS(DiagMsg);
+          OS << "Unexpected pattern while building a dependency "
+                "graph.\nInstruction: ";
+          MI->print(OS);
+          OS << "Operand: ";
+          Op.print(OS);
+          OS << "\nOperand definition: ";
+          VRegDef->print(OS);
+          report_fatal_error(DiagMsg.c_str());
+        }
         if (Reg2Entry.count(RegOp))
           E->addDep(Reg2Entry[RegOp]);
       }

llvm/lib/Target/SPIRV/SPIRVDuplicatesTracker.h

@@ -26,6 +26,7 @@
 
 namespace llvm {
 namespace SPIRV {
+class SPIRVInstrInfo;
 // NOTE: using MapVector instead of DenseMap because it helps getting
 // everything ordered in a stable manner for a price of extra (NumKeys)*PtrSize
 // memory and expensive removals which do not happen anyway.
@@ -35,8 +36,9 @@ class DTSortableEntry : public MapVector<const MachineFunction *, Register> {
   struct FlagsTy {
     unsigned IsFunc : 1;
     unsigned IsGV : 1;
+    unsigned IsConst : 1;
     // NOTE: bit-field default init is a C++20 feature.
-    FlagsTy() : IsFunc(0), IsGV(0) {}
+    FlagsTy() : IsFunc(0), IsGV(0), IsConst(0) {}
   };
   FlagsTy Flags;
 
@@ -45,8 +47,10 @@ class DTSortableEntry : public MapVector<const MachineFunction *, Register> {
   // require hoisting of params as well.
   bool getIsFunc() const { return Flags.IsFunc; }
   bool getIsGV() const { return Flags.IsGV; }
+  bool getIsConst() const { return Flags.IsConst; }
   void setIsFunc(bool V) { Flags.IsFunc = V; }
   void setIsGV(bool V) { Flags.IsGV = V; }
+  void setIsConst(bool V) { Flags.IsConst = V; }
 
   const SmallVector<DTSortableEntry *, 2> &getDeps() const { return Deps; }
   void addDep(DTSortableEntry *E) { Deps.push_back(E); }
@@ -160,6 +164,10 @@ template <typename KeyTy> class SPIRVDuplicatesTrackerBase {
                      typename std::remove_const<
                          typename std::remove_pointer<KeyTy>::type>::type>())
       Storage[V].setIsGV(true);
+    if (std::is_same<Constant,
+                     typename std::remove_const<
+                         typename std::remove_pointer<KeyTy>::type>::type>())
+      Storage[V].setIsConst(true);
   }
 
   Register find(KeyTy V, const MachineFunction *MF) const {
@@ -211,11 +219,12 @@ class SPIRVGeneralDuplicatesTracker {
 
   template <typename T>
   void prebuildReg2Entry(SPIRVDuplicatesTracker<T> &DT,
-                         SPIRVReg2EntryTy &Reg2Entry);
+                         SPIRVReg2EntryTy &Reg2Entry,
+                         const SPIRVInstrInfo *TII);
 
 public:
   void buildDepsGraph(std::vector<SPIRV::DTSortableEntry *> &Graph,
-                      MachineModuleInfo *MMI);
+                      const SPIRVInstrInfo *TII, MachineModuleInfo *MMI);
 
   void add(const Type *Ty, const MachineFunction *MF, Register R) {
     TT.add(unifyPtrType(Ty), MF, R);

llvm/lib/Target/SPIRV/SPIRVGlobalRegistry.h

@@ -152,8 +152,9 @@ class SPIRVGlobalRegistry {
   }
 
   void buildDepsGraph(std::vector<SPIRV::DTSortableEntry *> &Graph,
+                      const SPIRVInstrInfo *TII,
                       MachineModuleInfo *MMI = nullptr) {
-    DT.buildDepsGraph(Graph, MMI);
+    DT.buildDepsGraph(Graph, TII, MMI);
   }
 
   void setBound(unsigned V) { Bound = V; }

llvm/lib/Target/SPIRV/SPIRVModuleAnalysis.cpp

@@ -282,7 +282,7 @@ void SPIRVModuleAnalysis::collectGlobalEntities(
 void SPIRVModuleAnalysis::processDefInstrs(const Module &M) {
   std::vector<SPIRV::DTSortableEntry *> DepsGraph;
 
-  GR->buildDepsGraph(DepsGraph, SPVDumpDeps ? MMI : nullptr);
+  GR->buildDepsGraph(DepsGraph, TII, SPVDumpDeps ? MMI : nullptr);
 
   collectGlobalEntities(
       DepsGraph, SPIRV::MB_TypeConstVars,