LLVM 20.0.0git
CodeMetrics.h
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1//===- CodeMetrics.h - Code cost measurements -------------------*- C++ -*-===//
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 various weight measurements for code, helping
10// the Inliner and other passes decide whether to duplicate its contents.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_ANALYSIS_CODEMETRICS_H
15#define LLVM_ANALYSIS_CODEMETRICS_H
16
17#include "llvm/ADT/DenseMap.h"
19
20namespace llvm {
21class AssumptionCache;
22class BasicBlock;
23class Instruction;
24class Loop;
25class Function;
26template <class T> class SmallPtrSetImpl;
27class TargetTransformInfo;
28class Value;
29
31
32/// Utility to calculate the size and a few similar metrics for a set
33/// of basic blocks.
35 /// True if this function contains a call to setjmp or other functions
36 /// with attribute "returns twice" without having the attribute itself.
37 bool exposesReturnsTwice = false;
38
39 /// True if this function calls itself.
40 bool isRecursive = false;
41
42 /// True if this function cannot be duplicated.
43 ///
44 /// True if this function contains one or more indirect branches, or it contains
45 /// one or more 'noduplicate' instructions.
46 bool notDuplicatable = false;
47
48 /// The kind of convergence specified in this function.
50
51 /// True if this function calls alloca (in the C sense).
52 bool usesDynamicAlloca = false;
53
54 /// Code size cost of the analyzed blocks.
56
57 /// Number of analyzed blocks.
58 unsigned NumBlocks = false;
59
60 /// Keeps track of basic block code size estimates.
62
63 /// Keep track of the number of calls to 'big' functions.
64 unsigned NumCalls = false;
65
66 /// The number of calls to internal functions with a single caller.
67 ///
68 /// These are likely targets for future inlining, likely exposed by
69 /// interleaved devirtualization.
70 unsigned NumInlineCandidates = 0;
71
72 /// How many instructions produce vector values.
73 ///
74 /// The inliner is more aggressive with inlining vector kernels.
75 unsigned NumVectorInsts = 0;
76
77 /// How many 'ret' instructions the blocks contain.
78 unsigned NumRets = 0;
79
80 /// Add information about a block to the current state.
82 const SmallPtrSetImpl<const Value *> &EphValues,
83 bool PrepareForLTO = false, const Loop *L = nullptr);
84
85 /// Collect a loop's ephemeral values (those used only by an assume
86 /// or similar intrinsics in the loop).
87 static void collectEphemeralValues(const Loop *L, AssumptionCache *AC,
89
90 /// Collect a functions's ephemeral values (those used only by an
91 /// assume or similar intrinsics in the function).
92 static void collectEphemeralValues(const Function *L, AssumptionCache *AC,
94};
95
96}
97
98#endif
This file defines the DenseMap class.
This file defines an InstructionCost class that is used when calculating the cost of an instruction,...
A cache of @llvm.assume calls within a function.
LLVM Basic Block Representation.
Definition: BasicBlock.h:61
Represents a single loop in the control flow graph.
Definition: LoopInfo.h:44
A templated base class for SmallPtrSet which provides the typesafe interface that is common across al...
Definition: SmallPtrSet.h:347
This pass provides access to the codegen interfaces that are needed for IR-level transformations.
@ BasicBlock
Various leaf nodes.
Definition: ISDOpcodes.h:71
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
ConvergenceKind
Definition: CodeMetrics.h:30
Utility to calculate the size and a few similar metrics for a set of basic blocks.
Definition: CodeMetrics.h:34
bool usesDynamicAlloca
True if this function calls alloca (in the C sense).
Definition: CodeMetrics.h:52
unsigned NumBlocks
Number of analyzed blocks.
Definition: CodeMetrics.h:58
ConvergenceKind Convergence
The kind of convergence specified in this function.
Definition: CodeMetrics.h:49
bool notDuplicatable
True if this function cannot be duplicated.
Definition: CodeMetrics.h:46
unsigned NumInlineCandidates
The number of calls to internal functions with a single caller.
Definition: CodeMetrics.h:70
bool isRecursive
True if this function calls itself.
Definition: CodeMetrics.h:40
static void collectEphemeralValues(const Loop *L, AssumptionCache *AC, SmallPtrSetImpl< const Value * > &EphValues)
Collect a loop's ephemeral values (those used only by an assume or similar intrinsics in the loop).
Definition: CodeMetrics.cpp:71
unsigned NumRets
How many 'ret' instructions the blocks contain.
Definition: CodeMetrics.h:78
bool exposesReturnsTwice
True if this function contains a call to setjmp or other functions with attribute "returns twice" wit...
Definition: CodeMetrics.h:37
DenseMap< const BasicBlock *, InstructionCost > NumBBInsts
Keeps track of basic block code size estimates.
Definition: CodeMetrics.h:61
void analyzeBasicBlock(const BasicBlock *BB, const TargetTransformInfo &TTI, const SmallPtrSetImpl< const Value * > &EphValues, bool PrepareForLTO=false, const Loop *L=nullptr)
Add information about a block to the current state.
unsigned NumCalls
Keep track of the number of calls to 'big' functions.
Definition: CodeMetrics.h:64
unsigned NumVectorInsts
How many instructions produce vector values.
Definition: CodeMetrics.h:75
InstructionCost NumInsts
Code size cost of the analyzed blocks.
Definition: CodeMetrics.h:55