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diff --git a/contrib/llvm/lib/CodeGen/IntrinsicLowering.cpp b/contrib/llvm/lib/CodeGen/IntrinsicLowering.cpp
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+//===-- IntrinsicLowering.cpp - Intrinsic Lowering default implementation -===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the IntrinsicLowering class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/IntrinsicLowering.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Type.h"
+#include "llvm/Support/CallSite.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+template <class ArgIt>
+static void EnsureFunctionExists(Module &M, const char *Name,
+ ArgIt ArgBegin, ArgIt ArgEnd,
+ Type *RetTy) {
+ // Insert a correctly-typed definition now.
+ std::vector<Type *> ParamTys;
+ for (ArgIt I = ArgBegin; I != ArgEnd; ++I)
+ ParamTys.push_back(I->getType());
+ M.getOrInsertFunction(Name, FunctionType::get(RetTy, ParamTys, false));
+}
+
+static void EnsureFPIntrinsicsExist(Module &M, Function *Fn,
+ const char *FName,
+ const char *DName, const char *LDName) {
+ // Insert definitions for all the floating point types.
+ switch((int)Fn->arg_begin()->getType()->getTypeID()) {
+ case Type::FloatTyID:
+ EnsureFunctionExists(M, FName, Fn->arg_begin(), Fn->arg_end(),
+ Type::getFloatTy(M.getContext()));
+ break;
+ case Type::DoubleTyID:
+ EnsureFunctionExists(M, DName, Fn->arg_begin(), Fn->arg_end(),
+ Type::getDoubleTy(M.getContext()));
+ break;
+ case Type::X86_FP80TyID:
+ case Type::FP128TyID:
+ case Type::PPC_FP128TyID:
+ EnsureFunctionExists(M, LDName, Fn->arg_begin(), Fn->arg_end(),
+ Fn->arg_begin()->getType());
+ break;
+ }
+}
+
+/// ReplaceCallWith - This function is used when we want to lower an intrinsic
+/// call to a call of an external function. This handles hard cases such as
+/// when there was already a prototype for the external function, and if that
+/// prototype doesn't match the arguments we expect to pass in.
+template <class ArgIt>
+static CallInst *ReplaceCallWith(const char *NewFn, CallInst *CI,
+ ArgIt ArgBegin, ArgIt ArgEnd,
+ Type *RetTy) {
+ // If we haven't already looked up this function, check to see if the
+ // program already contains a function with this name.
+ Module *M = CI->getParent()->getParent()->getParent();
+ // Get or insert the definition now.
+ std::vector<Type *> ParamTys;
+ for (ArgIt I = ArgBegin; I != ArgEnd; ++I)
+ ParamTys.push_back((*I)->getType());
+ Constant* FCache = M->getOrInsertFunction(NewFn,
+ FunctionType::get(RetTy, ParamTys, false));
+
+ IRBuilder<> Builder(CI->getParent(), CI);
+ SmallVector<Value *, 8> Args(ArgBegin, ArgEnd);
+ CallInst *NewCI = Builder.CreateCall(FCache, Args);
+ NewCI->setName(CI->getName());
+ if (!CI->use_empty())
+ CI->replaceAllUsesWith(NewCI);
+ return NewCI;
+}
+
+// VisualStudio defines setjmp as _setjmp
+#if defined(_MSC_VER) && defined(setjmp) && \
+ !defined(setjmp_undefined_for_msvc)
+# pragma push_macro("setjmp")
+# undef setjmp
+# define setjmp_undefined_for_msvc
+#endif
+
+void IntrinsicLowering::AddPrototypes(Module &M) {
+ LLVMContext &Context = M.getContext();
+ for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
+ if (I->isDeclaration() && !I->use_empty())
+ switch (I->getIntrinsicID()) {
+ default: break;
+ case Intrinsic::setjmp:
+ EnsureFunctionExists(M, "setjmp", I->arg_begin(), I->arg_end(),
+ Type::getInt32Ty(M.getContext()));
+ break;
+ case Intrinsic::longjmp:
+ EnsureFunctionExists(M, "longjmp", I->arg_begin(), I->arg_end(),
+ Type::getVoidTy(M.getContext()));
+ break;
+ case Intrinsic::siglongjmp:
+ EnsureFunctionExists(M, "abort", I->arg_end(), I->arg_end(),
+ Type::getVoidTy(M.getContext()));
+ break;
+ case Intrinsic::memcpy:
+ M.getOrInsertFunction("memcpy",
+ Type::getInt8PtrTy(Context),
+ Type::getInt8PtrTy(Context),
+ Type::getInt8PtrTy(Context),
+ TD.getIntPtrType(Context), (Type *)0);
+ break;
+ case Intrinsic::memmove:
+ M.getOrInsertFunction("memmove",
+ Type::getInt8PtrTy(Context),
+ Type::getInt8PtrTy(Context),
+ Type::getInt8PtrTy(Context),
+ TD.getIntPtrType(Context), (Type *)0);
+ break;
+ case Intrinsic::memset:
+ M.getOrInsertFunction("memset",
+ Type::getInt8PtrTy(Context),
+ Type::getInt8PtrTy(Context),
+ Type::getInt32Ty(M.getContext()),
+ TD.getIntPtrType(Context), (Type *)0);
+ break;
+ case Intrinsic::sqrt:
+ EnsureFPIntrinsicsExist(M, I, "sqrtf", "sqrt", "sqrtl");
+ break;
+ case Intrinsic::sin:
+ EnsureFPIntrinsicsExist(M, I, "sinf", "sin", "sinl");
+ break;
+ case Intrinsic::cos:
+ EnsureFPIntrinsicsExist(M, I, "cosf", "cos", "cosl");
+ break;
+ case Intrinsic::pow:
+ EnsureFPIntrinsicsExist(M, I, "powf", "pow", "powl");
+ break;
+ case Intrinsic::log:
+ EnsureFPIntrinsicsExist(M, I, "logf", "log", "logl");
+ break;
+ case Intrinsic::log2:
+ EnsureFPIntrinsicsExist(M, I, "log2f", "log2", "log2l");
+ break;
+ case Intrinsic::log10:
+ EnsureFPIntrinsicsExist(M, I, "log10f", "log10", "log10l");
+ break;
+ case Intrinsic::exp:
+ EnsureFPIntrinsicsExist(M, I, "expf", "exp", "expl");
+ break;
+ case Intrinsic::exp2:
+ EnsureFPIntrinsicsExist(M, I, "exp2f", "exp2", "exp2l");
+ break;
+ }
+}
+
+/// LowerBSWAP - Emit the code to lower bswap of V before the specified
+/// instruction IP.
+static Value *LowerBSWAP(LLVMContext &Context, Value *V, Instruction *IP) {
+ assert(V->getType()->isIntegerTy() && "Can't bswap a non-integer type!");
+
+ unsigned BitSize = V->getType()->getPrimitiveSizeInBits();
+
+ IRBuilder<> Builder(IP->getParent(), IP);
+
+ switch(BitSize) {
+ default: llvm_unreachable("Unhandled type size of value to byteswap!");
+ case 16: {
+ Value *Tmp1 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 8),
+ "bswap.2");
+ Value *Tmp2 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 8),
+ "bswap.1");
+ V = Builder.CreateOr(Tmp1, Tmp2, "bswap.i16");
+ break;
+ }
+ case 32: {
+ Value *Tmp4 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 24),
+ "bswap.4");
+ Value *Tmp3 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 8),
+ "bswap.3");
+ Value *Tmp2 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 8),
+ "bswap.2");
+ Value *Tmp1 = Builder.CreateLShr(V,ConstantInt::get(V->getType(), 24),
+ "bswap.1");
+ Tmp3 = Builder.CreateAnd(Tmp3,
+ ConstantInt::get(Type::getInt32Ty(Context), 0xFF0000),
+ "bswap.and3");
+ Tmp2 = Builder.CreateAnd(Tmp2,
+ ConstantInt::get(Type::getInt32Ty(Context), 0xFF00),
+ "bswap.and2");
+ Tmp4 = Builder.CreateOr(Tmp4, Tmp3, "bswap.or1");
+ Tmp2 = Builder.CreateOr(Tmp2, Tmp1, "bswap.or2");
+ V = Builder.CreateOr(Tmp4, Tmp2, "bswap.i32");
+ break;
+ }
+ case 64: {
+ Value *Tmp8 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 56),
+ "bswap.8");
+ Value *Tmp7 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 40),
+ "bswap.7");
+ Value *Tmp6 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 24),
+ "bswap.6");
+ Value *Tmp5 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 8),
+ "bswap.5");
+ Value* Tmp4 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 8),
+ "bswap.4");
+ Value* Tmp3 = Builder.CreateLShr(V,
+ ConstantInt::get(V->getType(), 24),
+ "bswap.3");
+ Value* Tmp2 = Builder.CreateLShr(V,
+ ConstantInt::get(V->getType(), 40),
+ "bswap.2");
+ Value* Tmp1 = Builder.CreateLShr(V,
+ ConstantInt::get(V->getType(), 56),
+ "bswap.1");
+ Tmp7 = Builder.CreateAnd(Tmp7,
+ ConstantInt::get(Type::getInt64Ty(Context),
+ 0xFF000000000000ULL),
+ "bswap.and7");
+ Tmp6 = Builder.CreateAnd(Tmp6,
+ ConstantInt::get(Type::getInt64Ty(Context),
+ 0xFF0000000000ULL),
+ "bswap.and6");
+ Tmp5 = Builder.CreateAnd(Tmp5,
+ ConstantInt::get(Type::getInt64Ty(Context),
+ 0xFF00000000ULL),
+ "bswap.and5");
+ Tmp4 = Builder.CreateAnd(Tmp4,
+ ConstantInt::get(Type::getInt64Ty(Context),
+ 0xFF000000ULL),
+ "bswap.and4");
+ Tmp3 = Builder.CreateAnd(Tmp3,
+ ConstantInt::get(Type::getInt64Ty(Context),
+ 0xFF0000ULL),
+ "bswap.and3");
+ Tmp2 = Builder.CreateAnd(Tmp2,
+ ConstantInt::get(Type::getInt64Ty(Context),
+ 0xFF00ULL),
+ "bswap.and2");
+ Tmp8 = Builder.CreateOr(Tmp8, Tmp7, "bswap.or1");
+ Tmp6 = Builder.CreateOr(Tmp6, Tmp5, "bswap.or2");
+ Tmp4 = Builder.CreateOr(Tmp4, Tmp3, "bswap.or3");
+ Tmp2 = Builder.CreateOr(Tmp2, Tmp1, "bswap.or4");
+ Tmp8 = Builder.CreateOr(Tmp8, Tmp6, "bswap.or5");
+ Tmp4 = Builder.CreateOr(Tmp4, Tmp2, "bswap.or6");
+ V = Builder.CreateOr(Tmp8, Tmp4, "bswap.i64");
+ break;
+ }
+ }
+ return V;
+}
+
+/// LowerCTPOP - Emit the code to lower ctpop of V before the specified
+/// instruction IP.
+static Value *LowerCTPOP(LLVMContext &Context, Value *V, Instruction *IP) {
+ assert(V->getType()->isIntegerTy() && "Can't ctpop a non-integer type!");
+
+ static const uint64_t MaskValues[6] = {
+ 0x5555555555555555ULL, 0x3333333333333333ULL,
+ 0x0F0F0F0F0F0F0F0FULL, 0x00FF00FF00FF00FFULL,
+ 0x0000FFFF0000FFFFULL, 0x00000000FFFFFFFFULL
+ };
+
+ IRBuilder<> Builder(IP->getParent(), IP);
+
+ unsigned BitSize = V->getType()->getPrimitiveSizeInBits();
+ unsigned WordSize = (BitSize + 63) / 64;
+ Value *Count = ConstantInt::get(V->getType(), 0);
+
+ for (unsigned n = 0; n < WordSize; ++n) {
+ Value *PartValue = V;
+ for (unsigned i = 1, ct = 0; i < (BitSize>64 ? 64 : BitSize);
+ i <<= 1, ++ct) {
+ Value *MaskCst = ConstantInt::get(V->getType(), MaskValues[ct]);
+ Value *LHS = Builder.CreateAnd(PartValue, MaskCst, "cppop.and1");
+ Value *VShift = Builder.CreateLShr(PartValue,
+ ConstantInt::get(V->getType(), i),
+ "ctpop.sh");
+ Value *RHS = Builder.CreateAnd(VShift, MaskCst, "cppop.and2");
+ PartValue = Builder.CreateAdd(LHS, RHS, "ctpop.step");
+ }
+ Count = Builder.CreateAdd(PartValue, Count, "ctpop.part");
+ if (BitSize > 64) {
+ V = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 64),
+ "ctpop.part.sh");
+ BitSize -= 64;
+ }
+ }
+
+ return Count;
+}
+
+/// LowerCTLZ - Emit the code to lower ctlz of V before the specified
+/// instruction IP.
+static Value *LowerCTLZ(LLVMContext &Context, Value *V, Instruction *IP) {
+
+ IRBuilder<> Builder(IP->getParent(), IP);
+
+ unsigned BitSize = V->getType()->getPrimitiveSizeInBits();
+ for (unsigned i = 1; i < BitSize; i <<= 1) {
+ Value *ShVal = ConstantInt::get(V->getType(), i);
+ ShVal = Builder.CreateLShr(V, ShVal, "ctlz.sh");
+ V = Builder.CreateOr(V, ShVal, "ctlz.step");
+ }
+
+ V = Builder.CreateNot(V);
+ return LowerCTPOP(Context, V, IP);
+}
+
+static void ReplaceFPIntrinsicWithCall(CallInst *CI, const char *Fname,
+ const char *Dname,
+ const char *LDname) {
+ CallSite CS(CI);
+ switch (CI->getArgOperand(0)->getType()->getTypeID()) {
+ default: llvm_unreachable("Invalid type in intrinsic");
+ case Type::FloatTyID:
+ ReplaceCallWith(Fname, CI, CS.arg_begin(), CS.arg_end(),
+ Type::getFloatTy(CI->getContext()));
+ break;
+ case Type::DoubleTyID:
+ ReplaceCallWith(Dname, CI, CS.arg_begin(), CS.arg_end(),
+ Type::getDoubleTy(CI->getContext()));
+ break;
+ case Type::X86_FP80TyID:
+ case Type::FP128TyID:
+ case Type::PPC_FP128TyID:
+ ReplaceCallWith(LDname, CI, CS.arg_begin(), CS.arg_end(),
+ CI->getArgOperand(0)->getType());
+ break;
+ }
+}
+
+void IntrinsicLowering::LowerIntrinsicCall(CallInst *CI) {
+ IRBuilder<> Builder(CI->getParent(), CI);
+ LLVMContext &Context = CI->getContext();
+
+ const Function *Callee = CI->getCalledFunction();
+ assert(Callee && "Cannot lower an indirect call!");
+
+ CallSite CS(CI);
+ switch (Callee->getIntrinsicID()) {
+ case Intrinsic::not_intrinsic:
+ report_fatal_error("Cannot lower a call to a non-intrinsic function '"+
+ Callee->getName() + "'!");
+ default:
+ report_fatal_error("Code generator does not support intrinsic function '"+
+ Callee->getName()+"'!");
+
+ case Intrinsic::expect: {
+ // Just replace __builtin_expect(exp, c) with EXP.
+ Value *V = CI->getArgOperand(0);
+ CI->replaceAllUsesWith(V);
+ break;
+ }
+
+ // The setjmp/longjmp intrinsics should only exist in the code if it was
+ // never optimized (ie, right out of the CFE), or if it has been hacked on
+ // by the lowerinvoke pass. In both cases, the right thing to do is to
+ // convert the call to an explicit setjmp or longjmp call.
+ case Intrinsic::setjmp: {
+ Value *V = ReplaceCallWith("setjmp", CI, CS.arg_begin(), CS.arg_end(),
+ Type::getInt32Ty(Context));
+ if (!CI->getType()->isVoidTy())
+ CI->replaceAllUsesWith(V);
+ break;
+ }
+ case Intrinsic::sigsetjmp:
+ if (!CI->getType()->isVoidTy())
+ CI->replaceAllUsesWith(Constant::getNullValue(CI->getType()));
+ break;
+
+ case Intrinsic::longjmp: {
+ ReplaceCallWith("longjmp", CI, CS.arg_begin(), CS.arg_end(),
+ Type::getVoidTy(Context));
+ break;
+ }
+
+ case Intrinsic::siglongjmp: {
+ // Insert the call to abort
+ ReplaceCallWith("abort", CI, CS.arg_end(), CS.arg_end(),
+ Type::getVoidTy(Context));
+ break;
+ }
+ case Intrinsic::ctpop:
+ CI->replaceAllUsesWith(LowerCTPOP(Context, CI->getArgOperand(0), CI));
+ break;
+
+ case Intrinsic::bswap:
+ CI->replaceAllUsesWith(LowerBSWAP(Context, CI->getArgOperand(0), CI));
+ break;
+
+ case Intrinsic::ctlz:
+ CI->replaceAllUsesWith(LowerCTLZ(Context, CI->getArgOperand(0), CI));
+ break;
+
+ case Intrinsic::cttz: {
+ // cttz(x) -> ctpop(~X & (X-1))
+ Value *Src = CI->getArgOperand(0);
+ Value *NotSrc = Builder.CreateNot(Src);
+ NotSrc->setName(Src->getName() + ".not");
+ Value *SrcM1 = ConstantInt::get(Src->getType(), 1);
+ SrcM1 = Builder.CreateSub(Src, SrcM1);
+ Src = LowerCTPOP(Context, Builder.CreateAnd(NotSrc, SrcM1), CI);
+ CI->replaceAllUsesWith(Src);
+ break;
+ }
+
+ case Intrinsic::stacksave:
+ case Intrinsic::stackrestore: {
+ if (!Warned)
+ errs() << "WARNING: this target does not support the llvm.stack"
+ << (Callee->getIntrinsicID() == Intrinsic::stacksave ?
+ "save" : "restore") << " intrinsic.\n";
+ Warned = true;
+ if (Callee->getIntrinsicID() == Intrinsic::stacksave)
+ CI->replaceAllUsesWith(Constant::getNullValue(CI->getType()));
+ break;
+ }
+
+ case Intrinsic::returnaddress:
+ case Intrinsic::frameaddress:
+ errs() << "WARNING: this target does not support the llvm."
+ << (Callee->getIntrinsicID() == Intrinsic::returnaddress ?
+ "return" : "frame") << "address intrinsic.\n";
+ CI->replaceAllUsesWith(ConstantPointerNull::get(
+ cast<PointerType>(CI->getType())));
+ break;
+
+ case Intrinsic::prefetch:
+ break; // Simply strip out prefetches on unsupported architectures
+
+ case Intrinsic::pcmarker:
+ break; // Simply strip out pcmarker on unsupported architectures
+ case Intrinsic::readcyclecounter: {
+ errs() << "WARNING: this target does not support the llvm.readcyclecoun"
+ << "ter intrinsic. It is being lowered to a constant 0\n";
+ CI->replaceAllUsesWith(ConstantInt::get(Type::getInt64Ty(Context), 0));
+ break;
+ }
+
+ case Intrinsic::dbg_declare:
+ break; // Simply strip out debugging intrinsics
+
+ case Intrinsic::eh_typeid_for:
+ // Return something different to eh_selector.
+ CI->replaceAllUsesWith(ConstantInt::get(CI->getType(), 1));
+ break;
+
+ case Intrinsic::var_annotation:
+ break; // Strip out annotate intrinsic
+
+ case Intrinsic::memcpy: {
+ Type *IntPtr = TD.getIntPtrType(Context);
+ Value *Size = Builder.CreateIntCast(CI->getArgOperand(2), IntPtr,
+ /* isSigned */ false);
+ Value *Ops[3];
+ Ops[0] = CI->getArgOperand(0);
+ Ops[1] = CI->getArgOperand(1);
+ Ops[2] = Size;
+ ReplaceCallWith("memcpy", CI, Ops, Ops+3, CI->getArgOperand(0)->getType());
+ break;
+ }
+ case Intrinsic::memmove: {
+ Type *IntPtr = TD.getIntPtrType(Context);
+ Value *Size = Builder.CreateIntCast(CI->getArgOperand(2), IntPtr,
+ /* isSigned */ false);
+ Value *Ops[3];
+ Ops[0] = CI->getArgOperand(0);
+ Ops[1] = CI->getArgOperand(1);
+ Ops[2] = Size;
+ ReplaceCallWith("memmove", CI, Ops, Ops+3, CI->getArgOperand(0)->getType());
+ break;
+ }
+ case Intrinsic::memset: {
+ Type *IntPtr = TD.getIntPtrType(Context);
+ Value *Size = Builder.CreateIntCast(CI->getArgOperand(2), IntPtr,
+ /* isSigned */ false);
+ Value *Ops[3];
+ Ops[0] = CI->getArgOperand(0);
+ // Extend the amount to i32.
+ Ops[1] = Builder.CreateIntCast(CI->getArgOperand(1),
+ Type::getInt32Ty(Context),
+ /* isSigned */ false);
+ Ops[2] = Size;
+ ReplaceCallWith("memset", CI, Ops, Ops+3, CI->getArgOperand(0)->getType());
+ break;
+ }
+ case Intrinsic::sqrt: {
+ ReplaceFPIntrinsicWithCall(CI, "sqrtf", "sqrt", "sqrtl");
+ break;
+ }
+ case Intrinsic::log: {
+ ReplaceFPIntrinsicWithCall(CI, "logf", "log", "logl");
+ break;
+ }
+ case Intrinsic::log2: {
+ ReplaceFPIntrinsicWithCall(CI, "log2f", "log2", "log2l");
+ break;
+ }
+ case Intrinsic::log10: {
+ ReplaceFPIntrinsicWithCall(CI, "log10f", "log10", "log10l");
+ break;
+ }
+ case Intrinsic::exp: {
+ ReplaceFPIntrinsicWithCall(CI, "expf", "exp", "expl");
+ break;
+ }
+ case Intrinsic::exp2: {
+ ReplaceFPIntrinsicWithCall(CI, "exp2f", "exp2", "exp2l");
+ break;
+ }
+ case Intrinsic::pow: {
+ ReplaceFPIntrinsicWithCall(CI, "powf", "pow", "powl");
+ break;
+ }
+ case Intrinsic::flt_rounds:
+ // Lower to "round to the nearest"
+ if (!CI->getType()->isVoidTy())
+ CI->replaceAllUsesWith(ConstantInt::get(CI->getType(), 1));
+ break;
+ case Intrinsic::invariant_start:
+ case Intrinsic::lifetime_start:
+ // Discard region information.
+ CI->replaceAllUsesWith(UndefValue::get(CI->getType()));
+ break;
+ case Intrinsic::invariant_end:
+ case Intrinsic::lifetime_end:
+ // Discard region information.
+ break;
+ }
+
+ assert(CI->use_empty() &&
+ "Lowering should have eliminated any uses of the intrinsic call!");
+ CI->eraseFromParent();
+}
+
+bool IntrinsicLowering::LowerToByteSwap(CallInst *CI) {
+ // Verify this is a simple bswap.
+ if (CI->getNumArgOperands() != 1 ||
+ CI->getType() != CI->getArgOperand(0)->getType() ||
+ !CI->getType()->isIntegerTy())
+ return false;
+
+ IntegerType *Ty = dyn_cast<IntegerType>(CI->getType());
+ if (!Ty)
+ return false;
+
+ // Okay, we can do this xform, do so now.
+ Module *M = CI->getParent()->getParent()->getParent();
+ Constant *Int = Intrinsic::getDeclaration(M, Intrinsic::bswap, Ty);
+
+ Value *Op = CI->getArgOperand(0);
+ Op = CallInst::Create(Int, Op, CI->getName(), CI);
+
+ CI->replaceAllUsesWith(Op);
+ CI->eraseFromParent();
+ return true;
+}
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