[llvm][Transforms][Utils] Remove no-op ptr-to-ptr bitcasts (NFC)

Opaque ptr cleanup effort (NFC).

Author: JOE1994

llvm/lib/Transforms/Utils/InlineFunction.cpp

@@ -1951,8 +1951,7 @@ inlineRetainOrClaimRVCalls(CallBase &CB, objcarc::ARCInstKind RVCallKind,
           Builder.SetInsertPoint(II);
           Function *IFn =
               Intrinsic::getDeclaration(Mod, Intrinsic::objc_release);
-          Value *BC = Builder.CreateBitCast(RetOpnd, IFn->getArg(0)->getType());
-          Builder.CreateCall(IFn, BC, "");
+          Builder.CreateCall(IFn, RetOpnd, "");
         }
         II->eraseFromParent();
         InsertRetainCall = false;
@@ -1987,8 +1986,7 @@ inlineRetainOrClaimRVCalls(CallBase &CB, objcarc::ARCInstKind RVCallKind,
       // to objc_retain.
       Builder.SetInsertPoint(RI);
       Function *IFn = Intrinsic::getDeclaration(Mod, Intrinsic::objc_retain);
-      Value *BC = Builder.CreateBitCast(RetOpnd, IFn->getArg(0)->getType());
-      Builder.CreateCall(IFn, BC, "");
+      Builder.CreateCall(IFn, RetOpnd, "");
     }
   }
 }

llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp

@@ -1148,7 +1148,7 @@ Value *LibCallSimplifier::optimizeStrCSpn(CallInst *CI, IRBuilderBase &B) {
 Value *LibCallSimplifier::optimizeStrStr(CallInst *CI, IRBuilderBase &B) {
   // fold strstr(x, x) -> x.
   if (CI->getArgOperand(0) == CI->getArgOperand(1))
-    return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
+    return CI->getArgOperand(0);
 
   // fold strstr(a, b) == a -> strncmp(a, b, strlen(b)) == 0
   if (isOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
@@ -1176,7 +1176,7 @@ Value *LibCallSimplifier::optimizeStrStr(CallInst *CI, IRBuilderBase &B) {
 
   // fold strstr(x, "") -> x.
   if (HasStr2 && ToFindStr.empty())
-    return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
+    return CI->getArgOperand(0);
 
   // If both strings are known, constant fold it.
   if (HasStr1 && HasStr2) {
@@ -1186,16 +1186,13 @@ Value *LibCallSimplifier::optimizeStrStr(CallInst *CI, IRBuilderBase &B) {
       return Constant::getNullValue(CI->getType());
 
     // strstr("abcd", "bc") -> gep((char*)"abcd", 1)
-    Value *Result = CI->getArgOperand(0);
-    Result =
-        B.CreateConstInBoundsGEP1_64(B.getInt8Ty(), Result, Offset, "strstr");
-    return B.CreateBitCast(Result, CI->getType());
+    return B.CreateConstInBoundsGEP1_64(B.getInt8Ty(), CI->getArgOperand(0),
+                                        Offset, "strstr");
   }
 
   // fold strstr(x, "y") -> strchr(x, 'y').
   if (HasStr2 && ToFindStr.size() == 1) {
-    Value *StrChr = emitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TLI);
-    return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : nullptr;
+    return emitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TLI);
   }
 
   annotateNonNullNoUndefBasedOnAccess(CI, {0, 1});