Enable Ompopt (rust-lang#480)

* Enable openmpopt

* build omp only on 13+

Author: wsmoses

enzyme/Enzyme/Enzyme.cpp

@@ -64,6 +64,7 @@
 
 #if LLVM_VERSION_MAJOR >= 13
 #include "llvm/Transforms/IPO/Attributor.h"
+#include "llvm/Transforms/IPO/OpenMPOpt.h"
 #endif
 
 #include "CApi.h"
@@ -80,6 +81,10 @@ llvm::cl::opt<bool>
 llvm::cl::opt<bool> EnzymeAttributor("enzyme-attributor", cl::init(false),
                                      cl::Hidden,
                                      cl::desc("Run attributor post Enzyme"));
+
+llvm::cl::opt<bool> EnzymeOMPOpt("enzyme-omp-opt", cl::init(true), cl::Hidden,
+                                 cl::desc("Whether to enable openmp opt"));
+
 #if LLVM_VERSION_MAJOR >= 14
 #define addAttribute addAttributeAtIndex
 #endif
@@ -1736,6 +1741,14 @@ class Enzyme : public ModulePass {
         I->eraseFromParent();
       }
     }
+
+#if LLVM_VERSION_MAJOR >= 13
+    if (PostOpt && EnzymeOMPOpt) {
+      OpenMPOptPass().run(M, Logic.PPC.MAM);
+      changed = true;
+    }
+#endif
+
     std::set<Function *> done;
     for (Function &F : M) {
       if (F.empty())
@@ -1794,6 +1807,13 @@ class Enzyme : public ModulePass {
       changed = true;
     }
 
+#if LLVM_VERSION_MAJOR >= 13
+    if (PostOpt && EnzymeOMPOpt) {
+      OpenMPOptPass().run(M, Logic.PPC.MAM);
+      changed = true;
+    }
+#endif
+
     Logic.clear();
     return changed;
   }

enzyme/Enzyme/FunctionUtils.cpp

@@ -920,6 +920,7 @@ PreProcessCache::PreProcessCache() {
   FAM.registerPass([] { return OptimizationRemarkEmitterAnalysis(); });
   FAM.registerPass([] { return LazyValueAnalysis(); });
 #if LLVM_VERSION_MAJOR >= 8
+  MAM.registerPass([] { return PassInstrumentationAnalysis(); });
   FAM.registerPass([] { return PassInstrumentationAnalysis(); });
 #endif
 

enzyme/Enzyme/TypeAnalysis/TypeAnalysis.cpp

@@ -842,6 +842,22 @@ void TypeAnalyzer::considerTBAA() {
           updateAnalysis(call->getOperand(0), update, call);
           updateAnalysis(call->getOperand(1), update, call);
           continue;
+        } else if (call->getCalledFunction() &&
+                   (call->getCalledFunction()->getIntrinsicID() ==
+                    Intrinsic::memset)) {
+          int64_t copySize = 1;
+          for (auto val : fntypeinfo.knownIntegralValues(call->getOperand(2),
+                                                         DT, intseen, SE)) {
+            copySize = max(copySize, val);
+          }
+          TypeTree update =
+              vdptr
+                  .ShiftIndices(DL, /*init offset*/ 0,
+                                /*max size*/ copySize, /*new offset*/ 0)
+                  .Only(-1);
+
+          updateAnalysis(call->getOperand(0), update, call);
+          continue;
         } else if (call->getCalledFunction() &&
                    call->getCalledFunction()->getIntrinsicID() ==
                        Intrinsic::masked_gather) {