1 //===- VectorBuilder.cpp - Builder for VP Intrinsics ----------------------===//
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 // This file implements the VectorBuilder class, which is used as a convenient
10 // way to create VP intrinsics as if they were LLVM instructions with a
11 // consistent and simplified interface.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include <llvm/ADT/SmallVector.h>
16 #include <llvm/IR/FPEnv.h>
17 #include <llvm/IR/Instructions.h>
18 #include <llvm/IR/IntrinsicInst.h>
19 #include <llvm/IR/Intrinsics.h>
20 #include <llvm/IR/VectorBuilder.h>
21 
22 namespace llvm {
23 
24 void VectorBuilder::handleError(const char *ErrorMsg) const {
25   if (ErrorHandling == Behavior::SilentlyReturnNone)
26     return;
27   report_fatal_error(ErrorMsg);
28 }
29 
30 Module &VectorBuilder::getModule() const {
31   return *Builder.GetInsertBlock()->getModule();
32 }
33 
34 Value *VectorBuilder::getAllTrueMask() {
35   auto *BoolTy = Builder.getInt1Ty();
36   auto *MaskTy = VectorType::get(BoolTy, StaticVectorLength);
37   return ConstantInt::getAllOnesValue(MaskTy);
38 }
39 
40 Value &VectorBuilder::requestMask() {
41   if (Mask)
42     return *Mask;
43 
44   return *getAllTrueMask();
45 }
46 
47 Value &VectorBuilder::requestEVL() {
48   if (ExplicitVectorLength)
49     return *ExplicitVectorLength;
50 
51   assert(!StaticVectorLength.isScalable() && "TODO vscale lowering");
52   auto *IntTy = Builder.getInt32Ty();
53   return *ConstantInt::get(IntTy, StaticVectorLength.getFixedValue());
54 }
55 
56 Value *VectorBuilder::createVectorInstruction(unsigned Opcode, Type *ReturnTy,
57                                               ArrayRef<Value *> InstOpArray,
58                                               const Twine &Name) {
59   auto VPID = VPIntrinsic::getForOpcode(Opcode);
60   if (VPID == Intrinsic::not_intrinsic)
61     return returnWithError<Value *>("No VPIntrinsic for this opcode");
62 
63   auto MaskPosOpt = VPIntrinsic::getMaskParamPos(VPID);
64   auto VLenPosOpt = VPIntrinsic::getVectorLengthParamPos(VPID);
65   size_t NumInstParams = InstOpArray.size();
66   size_t NumVPParams =
67       NumInstParams + MaskPosOpt.has_value() + VLenPosOpt.has_value();
68 
69   SmallVector<Value *, 6> IntrinParams;
70 
71   // Whether the mask and vlen parameter are at the end of the parameter list.
72   bool TrailingMaskAndVLen =
73       std::min<size_t>(MaskPosOpt.value_or(NumInstParams),
74                        VLenPosOpt.value_or(NumInstParams)) >= NumInstParams;
75 
76   if (TrailingMaskAndVLen) {
77     // Fast path for trailing mask, vector length.
78     IntrinParams.append(InstOpArray.begin(), InstOpArray.end());
79     IntrinParams.resize(NumVPParams);
80   } else {
81     IntrinParams.resize(NumVPParams);
82     // Insert mask and evl operands in between the instruction operands.
83     for (size_t VPParamIdx = 0, ParamIdx = 0; VPParamIdx < NumVPParams;
84          ++VPParamIdx) {
85       if ((MaskPosOpt && MaskPosOpt.value_or(NumVPParams) == VPParamIdx) ||
86           (VLenPosOpt && VLenPosOpt.value_or(NumVPParams) == VPParamIdx))
87         continue;
88       assert(ParamIdx < NumInstParams);
89       IntrinParams[VPParamIdx] = InstOpArray[ParamIdx++];
90     }
91   }
92 
93   if (MaskPosOpt)
94     IntrinParams[*MaskPosOpt] = &requestMask();
95   if (VLenPosOpt)
96     IntrinParams[*VLenPosOpt] = &requestEVL();
97 
98   auto *VPDecl = VPIntrinsic::getDeclarationForParams(&getModule(), VPID,
99                                                       ReturnTy, IntrinParams);
100   return Builder.CreateCall(VPDecl, IntrinParams, Name);
101 }
102 
103 } // namespace llvm
104