• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===-- InstrinsicInst.cpp - Intrinsic Instruction Wrappers ---------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements methods that make it really easy to deal with intrinsic
11 // functions.
12 //
13 // All intrinsic function calls are instances of the call instruction, so these
14 // are all subclasses of the CallInst class.  Note that none of these classes
15 // has state or virtual methods, which is an important part of this gross/neat
16 // hack working.
17 //
18 // In some cases, arguments to intrinsics need to be generic and are defined as
19 // type pointer to empty struct { }*.  To access the real item of interest the
20 // cast instruction needs to be stripped away.
21 //
22 //===----------------------------------------------------------------------===//
23 
24 #include "llvm/IR/IntrinsicInst.h"
25 #include "llvm/ADT/StringSwitch.h"
26 #include "llvm/IR/Constants.h"
27 #include "llvm/IR/DebugInfoMetadata.h"
28 #include "llvm/IR/GlobalVariable.h"
29 #include "llvm/IR/Metadata.h"
30 #include "llvm/IR/Module.h"
31 #include "llvm/Support/raw_ostream.h"
32 using namespace llvm;
33 
34 //===----------------------------------------------------------------------===//
35 /// DbgInfoIntrinsic - This is the common base class for debug info intrinsics
36 ///
37 
getVariableLocation(bool AllowNullOp) const38 Value *DbgInfoIntrinsic::getVariableLocation(bool AllowNullOp) const {
39   Value *Op = getArgOperand(0);
40   if (AllowNullOp && !Op)
41     return nullptr;
42 
43   auto *MD = cast<MetadataAsValue>(Op)->getMetadata();
44   if (auto *V = dyn_cast<ValueAsMetadata>(MD))
45     return V->getValue();
46 
47   // When the value goes to null, it gets replaced by an empty MDNode.
48   assert((isa<DbgLabelInst>(this)
49           || !cast<MDNode>(MD)->getNumOperands())
50 	 && "DbgValueInst Expected an empty MDNode");
51 
52   return nullptr;
53 }
54 
getFragmentSizeInBits() const55 Optional<uint64_t> DbgInfoIntrinsic::getFragmentSizeInBits() const {
56   if (auto Fragment = getExpression()->getFragmentInfo())
57     return Fragment->SizeInBits;
58   return getVariable()->getSizeInBits();
59 }
60 
lookupLLVMIntrinsicByName(ArrayRef<const char * > NameTable,StringRef Name)61 int llvm::Intrinsic::lookupLLVMIntrinsicByName(ArrayRef<const char *> NameTable,
62                                                StringRef Name) {
63   assert(Name.startswith("llvm."));
64 
65   // Do successive binary searches of the dotted name components. For
66   // "llvm.gc.experimental.statepoint.p1i8.p1i32", we will find the range of
67   // intrinsics starting with "llvm.gc", then "llvm.gc.experimental", then
68   // "llvm.gc.experimental.statepoint", and then we will stop as the range is
69   // size 1. During the search, we can skip the prefix that we already know is
70   // identical. By using strncmp we consider names with differing suffixes to
71   // be part of the equal range.
72   size_t CmpStart = 0;
73   size_t CmpEnd = 4; // Skip the "llvm" component.
74   const char *const *Low = NameTable.begin();
75   const char *const *High = NameTable.end();
76   const char *const *LastLow = Low;
77   while (CmpEnd < Name.size() && High - Low > 0) {
78     CmpStart = CmpEnd;
79     CmpEnd = Name.find('.', CmpStart + 1);
80     CmpEnd = CmpEnd == StringRef::npos ? Name.size() : CmpEnd;
81     auto Cmp = [CmpStart, CmpEnd](const char *LHS, const char *RHS) {
82       return strncmp(LHS + CmpStart, RHS + CmpStart, CmpEnd - CmpStart) < 0;
83     };
84     LastLow = Low;
85     std::tie(Low, High) = std::equal_range(Low, High, Name.data(), Cmp);
86   }
87   if (High - Low > 0)
88     LastLow = Low;
89 
90   if (LastLow == NameTable.end())
91     return -1;
92   StringRef NameFound = *LastLow;
93   if (Name == NameFound ||
94       (Name.startswith(NameFound) && Name[NameFound.size()] == '.'))
95     return LastLow - NameTable.begin();
96   return -1;
97 }
98 
getStep() const99 Value *InstrProfIncrementInst::getStep() const {
100   if (InstrProfIncrementInstStep::classof(this)) {
101     return const_cast<Value *>(getArgOperand(4));
102   }
103   const Module *M = getModule();
104   LLVMContext &Context = M->getContext();
105   return ConstantInt::get(Type::getInt64Ty(Context), 1);
106 }
107 
108 ConstrainedFPIntrinsic::RoundingMode
getRoundingMode() const109 ConstrainedFPIntrinsic::getRoundingMode() const {
110   unsigned NumOperands = getNumArgOperands();
111   Metadata *MD =
112       dyn_cast<MetadataAsValue>(getArgOperand(NumOperands - 2))->getMetadata();
113   if (!MD || !isa<MDString>(MD))
114     return rmInvalid;
115   StringRef RoundingArg = cast<MDString>(MD)->getString();
116 
117   // For dynamic rounding mode, we use round to nearest but we will set the
118   // 'exact' SDNodeFlag so that the value will not be rounded.
119   return StringSwitch<RoundingMode>(RoundingArg)
120     .Case("round.dynamic",    rmDynamic)
121     .Case("round.tonearest",  rmToNearest)
122     .Case("round.downward",   rmDownward)
123     .Case("round.upward",     rmUpward)
124     .Case("round.towardzero", rmTowardZero)
125     .Default(rmInvalid);
126 }
127 
128 ConstrainedFPIntrinsic::ExceptionBehavior
getExceptionBehavior() const129 ConstrainedFPIntrinsic::getExceptionBehavior() const {
130   unsigned NumOperands = getNumArgOperands();
131   Metadata *MD =
132       dyn_cast<MetadataAsValue>(getArgOperand(NumOperands - 1))->getMetadata();
133   if (!MD || !isa<MDString>(MD))
134     return ebInvalid;
135   StringRef ExceptionArg = cast<MDString>(MD)->getString();
136   return StringSwitch<ExceptionBehavior>(ExceptionArg)
137     .Case("fpexcept.ignore",  ebIgnore)
138     .Case("fpexcept.maytrap", ebMayTrap)
139     .Case("fpexcept.strict",  ebStrict)
140     .Default(ebInvalid);
141 }
142 
isUnaryOp() const143 bool ConstrainedFPIntrinsic::isUnaryOp() const {
144   switch (getIntrinsicID()) {
145     default:
146       return false;
147     case Intrinsic::experimental_constrained_sqrt:
148     case Intrinsic::experimental_constrained_sin:
149     case Intrinsic::experimental_constrained_cos:
150     case Intrinsic::experimental_constrained_exp:
151     case Intrinsic::experimental_constrained_exp2:
152     case Intrinsic::experimental_constrained_log:
153     case Intrinsic::experimental_constrained_log10:
154     case Intrinsic::experimental_constrained_log2:
155     case Intrinsic::experimental_constrained_rint:
156     case Intrinsic::experimental_constrained_nearbyint:
157       return true;
158   }
159 }
160 
isTernaryOp() const161 bool ConstrainedFPIntrinsic::isTernaryOp() const {
162   switch (getIntrinsicID()) {
163     default:
164       return false;
165     case Intrinsic::experimental_constrained_fma:
166       return true;
167   }
168 }
169 
170