LLVM 19.0.0git
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 Loop;
24class Function;
25template <class T> class SmallPtrSetImpl;
26class TargetTransformInfo;
27class Value;
28
29/// Utility to calculate the size and a few similar metrics for a set
30/// of basic blocks.
32 /// True if this function contains a call to setjmp or other functions
33 /// with attribute "returns twice" without having the attribute itself.
34 bool exposesReturnsTwice = false;
35
36 /// True if this function calls itself.
37 bool isRecursive = false;
38
39 /// True if this function cannot be duplicated.
40 ///
41 /// True if this function contains one or more indirect branches, or it contains
42 /// one or more 'noduplicate' instructions.
43 bool notDuplicatable = false;
44
45 /// True if this function contains a call to a convergent function.
46 bool convergent = false;
47
48 /// True if this function calls alloca (in the C sense).
49 bool usesDynamicAlloca = false;
50
51 /// Code size cost of the analyzed blocks.
53
54 /// Number of analyzed blocks.
55 unsigned NumBlocks = false;
56
57 /// Keeps track of basic block code size estimates.
59
60 /// Keep track of the number of calls to 'big' functions.
61 unsigned NumCalls = false;
62
63 /// The number of calls to internal functions with a single caller.
64 ///
65 /// These are likely targets for future inlining, likely exposed by
66 /// interleaved devirtualization.
67 unsigned NumInlineCandidates = 0;
68
69 /// How many instructions produce vector values.
70 ///
71 /// The inliner is more aggressive with inlining vector kernels.
72 unsigned NumVectorInsts = 0;
73
74 /// How many 'ret' instructions the blocks contain.
75 unsigned NumRets = 0;
76
77 /// Add information about a block to the current state.
79 const SmallPtrSetImpl<const Value *> &EphValues,
80 bool PrepareForLTO = false);
81
82 /// Collect a loop's ephemeral values (those used only by an assume
83 /// or similar intrinsics in the loop).
84 static void collectEphemeralValues(const Loop *L, AssumptionCache *AC,
86
87 /// Collect a functions's ephemeral values (those used only by an
88 /// assume or similar intrinsics in the function).
89 static void collectEphemeralValues(const Function *L, AssumptionCache *AC,
91};
92
93}
94
95#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:60
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:321
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
Utility to calculate the size and a few similar metrics for a set of basic blocks.
Definition: CodeMetrics.h:31
bool usesDynamicAlloca
True if this function calls alloca (in the C sense).
Definition: CodeMetrics.h:49
unsigned NumBlocks
Number of analyzed blocks.
Definition: CodeMetrics.h:55
bool notDuplicatable
True if this function cannot be duplicated.
Definition: CodeMetrics.h:43
unsigned NumInlineCandidates
The number of calls to internal functions with a single caller.
Definition: CodeMetrics.h:67
bool isRecursive
True if this function calls itself.
Definition: CodeMetrics.h:37
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:70
unsigned NumRets
How many 'ret' instructions the blocks contain.
Definition: CodeMetrics.h:75
bool exposesReturnsTwice
True if this function contains a call to setjmp or other functions with attribute "returns twice" wit...
Definition: CodeMetrics.h:34
void analyzeBasicBlock(const BasicBlock *BB, const TargetTransformInfo &TTI, const SmallPtrSetImpl< const Value * > &EphValues, bool PrepareForLTO=false)
Add information about a block to the current state.
DenseMap< const BasicBlock *, InstructionCost > NumBBInsts
Keeps track of basic block code size estimates.
Definition: CodeMetrics.h:58
bool convergent
True if this function contains a call to a convergent function.
Definition: CodeMetrics.h:46
unsigned NumCalls
Keep track of the number of calls to 'big' functions.
Definition: CodeMetrics.h:61
unsigned NumVectorInsts
How many instructions produce vector values.
Definition: CodeMetrics.h:72
InstructionCost NumInsts
Code size cost of the analyzed blocks.
Definition: CodeMetrics.h:52