1//===- ReduceInstructionFlags.cpp - Specialized Delta Pass ----------------===//
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// Try to remove optimization flags on instructions
10//
11//===----------------------------------------------------------------------===//
12
13#include "ReduceInstructionFlags.h"
14#include "llvm/IR/InstIterator.h"
15#include "llvm/IR/Instruction.h"
16#include "llvm/IR/Instructions.h"
17#include "llvm/IR/Operator.h"
18
19using namespace llvm;
20
21void llvm::reduceInstructionFlagsDeltaPass(Oracle &O,
22 ReducerWorkItem &WorkItem) {
23 // Keep this in sync with computeIRComplexityScoreImpl().
24 for (Function &F : WorkItem.getModule()) {
25 for (Instruction &I : instructions(F)) {
26 if (auto *OBO = dyn_cast<OverflowingBinaryOperator>(Val: &I)) {
27 if (OBO->hasNoSignedWrap() && !O.shouldKeep())
28 I.setHasNoSignedWrap(false);
29 if (OBO->hasNoUnsignedWrap() && !O.shouldKeep())
30 I.setHasNoUnsignedWrap(false);
31 } else if (auto *Trunc = dyn_cast<TruncInst>(Val: &I)) {
32 if (Trunc->hasNoSignedWrap() && !O.shouldKeep())
33 Trunc->setHasNoSignedWrap(false);
34 if (Trunc->hasNoUnsignedWrap() && !O.shouldKeep())
35 Trunc->setHasNoUnsignedWrap(false);
36 } else if (auto *PE = dyn_cast<PossiblyExactOperator>(Val: &I)) {
37 if (PE->isExact() && !O.shouldKeep())
38 I.setIsExact(false);
39 } else if (auto *NNI = dyn_cast<PossiblyNonNegInst>(Val: &I)) {
40 if (NNI->hasNonNeg() && !O.shouldKeep())
41 NNI->setNonNeg(false);
42 } else if (auto *PDI = dyn_cast<PossiblyDisjointInst>(Val: &I)) {
43 if (PDI->isDisjoint() && !O.shouldKeep())
44 PDI->setIsDisjoint(false);
45 } else if (auto *ICmp = dyn_cast<ICmpInst>(Val: &I)) {
46 if (ICmp->hasSameSign() && !O.shouldKeep())
47 ICmp->setSameSign(false);
48 } else if (auto *GEP = dyn_cast<GetElementPtrInst>(Val: &I)) {
49 GEPNoWrapFlags NW = GEP->getNoWrapFlags();
50 if (NW.isInBounds() && !O.shouldKeep())
51 NW = NW.withoutInBounds();
52 if (NW.hasNoUnsignedSignedWrap() && !O.shouldKeep())
53 NW = NW.withoutNoUnsignedSignedWrap();
54 if (NW.hasNoUnsignedWrap() && !O.shouldKeep())
55 NW = NW.withoutNoUnsignedWrap();
56 GEP->setNoWrapFlags(NW);
57 } else if (auto *FPOp = dyn_cast<FPMathOperator>(Val: &I)) {
58 FastMathFlags Flags = FPOp->getFastMathFlags();
59
60 if (Flags.allowReassoc() && !O.shouldKeep())
61 Flags.setAllowReassoc(false);
62
63 if (Flags.noNaNs() && !O.shouldKeep())
64 Flags.setNoNaNs(false);
65
66 if (Flags.noInfs() && !O.shouldKeep())
67 Flags.setNoInfs(false);
68
69 if (Flags.noSignedZeros() && !O.shouldKeep())
70 Flags.setNoSignedZeros(false);
71
72 if (Flags.allowReciprocal() && !O.shouldKeep())
73 Flags.setAllowReciprocal(false);
74
75 if (Flags.allowContract() && !O.shouldKeep())
76 Flags.setAllowContract(false);
77
78 if (Flags.approxFunc() && !O.shouldKeep())
79 Flags.setApproxFunc(false);
80
81 I.copyFastMathFlags(FMF: Flags);
82 }
83 }
84 }
85}
86