Remove dead code in the HexagonMCInst classes. This also fixes
[oota-llvm.git] / lib / Transforms / InstCombine / InstCombineCalls.cpp
index c42202a2fa6cfdaf6d850cf51536b6385ed83237..87dc8621a95b2c3dace89b9bae05a81dadf25e63 100644 (file)
@@ -11,7 +11,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "InstCombine.h"
+#include "InstCombineInternal.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/MemoryBuiltins.h"
 #include "llvm/IR/CallSite.h"
@@ -21,6 +21,7 @@
 #include "llvm/IR/Statepoint.h"
 #include "llvm/Transforms/Utils/BuildLibCalls.h"
 #include "llvm/Transforms/Utils/Local.h"
+#include "llvm/Transforms/Utils/SimplifyLibCalls.h"
 using namespace llvm;
 using namespace PatternMatch;
 
@@ -352,33 +353,11 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
     break;
   case Intrinsic::uadd_with_overflow: {
     Value *LHS = II->getArgOperand(0), *RHS = II->getArgOperand(1);
-    IntegerType *IT = cast<IntegerType>(II->getArgOperand(0)->getType());
-    uint32_t BitWidth = IT->getBitWidth();
-    APInt LHSKnownZero(BitWidth, 0);
-    APInt LHSKnownOne(BitWidth, 0);
-    computeKnownBits(LHS, LHSKnownZero, LHSKnownOne, 0, II);
-    bool LHSKnownNegative = LHSKnownOne[BitWidth - 1];
-    bool LHSKnownPositive = LHSKnownZero[BitWidth - 1];
-
-    if (LHSKnownNegative || LHSKnownPositive) {
-      APInt RHSKnownZero(BitWidth, 0);
-      APInt RHSKnownOne(BitWidth, 0);
-      computeKnownBits(RHS, RHSKnownZero, RHSKnownOne, 0, II);
-      bool RHSKnownNegative = RHSKnownOne[BitWidth - 1];
-      bool RHSKnownPositive = RHSKnownZero[BitWidth - 1];
-      if (LHSKnownNegative && RHSKnownNegative) {
-        // The sign bit is set in both cases: this MUST overflow.
-        // Create a simple add instruction, and insert it into the struct.
-        return CreateOverflowTuple(II, Builder->CreateAdd(LHS, RHS), true,
-                                    /*ReUseName*/true);
-      }
-
-      if (LHSKnownPositive && RHSKnownPositive) {
-        // The sign bit is clear in both cases: this CANNOT overflow.
-        // Create a simple add instruction, and insert it into the struct.
-        return CreateOverflowTuple(II, Builder->CreateNUWAdd(LHS, RHS), false);
-      }
-    }
+    OverflowResult OR = computeOverflowForUnsignedAdd(LHS, RHS, II);
+    if (OR == OverflowResult::NeverOverflows)
+      return CreateOverflowTuple(II, Builder->CreateNUWAdd(LHS, RHS), false);
+    if (OR == OverflowResult::AlwaysOverflows)
+      return CreateOverflowTuple(II, Builder->CreateAdd(LHS, RHS), true);
   }
   // FALL THROUGH uadd into sadd
   case Intrinsic::sadd_with_overflow:
@@ -1206,7 +1185,11 @@ static bool isSafeToEliminateVarargsCast(const CallSite CS,
 Instruction *InstCombiner::tryOptimizeCall(CallInst *CI, const DataLayout *DL) {
   if (!CI->getCalledFunction()) return nullptr;
 
-  if (Value *With = Simplifier->optimizeCall(CI)) {
+  auto InstCombineRAUW = [this](Instruction *From, Value *With) {
+    ReplaceInstUsesWith(*From, With);
+  };
+  LibCallSimplifier Simplifier(DL, TLI, InstCombineRAUW);
+  if (Value *With = Simplifier.optimizeCall(CI)) {
     ++NumSimplified;
     return CI->use_empty() ? CI : ReplaceInstUsesWith(*CI, With);
   }
@@ -1398,6 +1381,10 @@ bool InstCombiner::transformConstExprCastCall(CallSite CS) {
     dyn_cast<Function>(CS.getCalledValue()->stripPointerCasts());
   if (!Callee)
     return false;
+  // The prototype of thunks are a lie, don't try to directly call such
+  // functions.
+  if (Callee->hasFnAttribute("thunk"))
+    return false;
   Instruction *Caller = CS.getInstruction();
   const AttributeSet &CallerPAL = CS.getAttributes();