1 //===-- llvm/CodeGen/LowLevelTypeUtils.cpp --------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 /// \file This file implements the more header-heavy bits of the LLT class to
10 /// avoid polluting users' namespaces.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/CodeGen/LowLevelTypeUtils.h"
15 #include "llvm/ADT/APFloat.h"
16 #include "llvm/IR/DataLayout.h"
17 #include "llvm/IR/DerivedTypes.h"
18 using namespace llvm;
19 
20 LLT llvm::getLLTForType(Type &Ty, const DataLayout &DL) {
21   if (auto VTy = dyn_cast<VectorType>(&Ty)) {
22     auto EC = VTy->getElementCount();
23     LLT ScalarTy = getLLTForType(*VTy->getElementType(), DL);
24     if (EC.isScalar())
25       return ScalarTy;
26     return LLT::vector(EC, ScalarTy);
27   }
28 
29   if (auto PTy = dyn_cast<PointerType>(&Ty)) {
30     unsigned AddrSpace = PTy->getAddressSpace();
31     return LLT::pointer(AddrSpace, DL.getPointerSizeInBits(AddrSpace));
32   }
33 
34   if (Ty.isSized() && !Ty.isScalableTargetExtTy()) {
35     // Aggregates are no different from real scalars as far as GlobalISel is
36     // concerned.
37     auto SizeInBits = DL.getTypeSizeInBits(&Ty);
38     assert(SizeInBits != 0 && "invalid zero-sized type");
39     return LLT::scalar(SizeInBits);
40   }
41 
42   return LLT();
43 }
44 
45 MVT llvm::getMVTForLLT(LLT Ty) {
46   if (!Ty.isVector())
47     return MVT::getIntegerVT(Ty.getSizeInBits());
48 
49   return MVT::getVectorVT(
50       MVT::getIntegerVT(Ty.getElementType().getSizeInBits()),
51       Ty.getNumElements());
52 }
53 
54 EVT llvm::getApproximateEVTForLLT(LLT Ty, const DataLayout &DL,
55                                   LLVMContext &Ctx) {
56   if (Ty.isVector()) {
57     EVT EltVT = getApproximateEVTForLLT(Ty.getElementType(), DL, Ctx);
58     return EVT::getVectorVT(Ctx, EltVT, Ty.getElementCount());
59   }
60 
61   return EVT::getIntegerVT(Ctx, Ty.getSizeInBits());
62 }
63 
64 LLT llvm::getLLTForMVT(MVT Ty) {
65   if (!Ty.isVector())
66     return LLT::scalar(Ty.getSizeInBits());
67 
68   return LLT::scalarOrVector(Ty.getVectorElementCount(),
69                              Ty.getVectorElementType().getSizeInBits());
70 }
71 
72 const llvm::fltSemantics &llvm::getFltSemanticForLLT(LLT Ty) {
73   assert(Ty.isScalar() && "Expected a scalar type.");
74   switch (Ty.getSizeInBits()) {
75   case 16:
76     return APFloat::IEEEhalf();
77   case 32:
78     return APFloat::IEEEsingle();
79   case 64:
80     return APFloat::IEEEdouble();
81   case 128:
82     return APFloat::IEEEquad();
83   }
84   llvm_unreachable("Invalid FP type size.");
85 }
86