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" |
18 | #include "llvm/Support/InstructionCost.h" |
19 | |
20 | namespace llvm { |
21 | class AssumptionCache; |
22 | class BasicBlock; |
23 | class Loop; |
24 | class Function; |
25 | template <class T> class SmallPtrSetImpl; |
26 | class TargetTransformInfo; |
27 | class Value; |
28 | |
29 | /// Utility to calculate the size and a few similar metrics for a set |
30 | /// of basic blocks. |
31 | struct CodeMetrics { |
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. |
52 | InstructionCost NumInsts = 0; |
53 | |
54 | /// Number of analyzed blocks. |
55 | unsigned NumBlocks = false; |
56 | |
57 | /// Keeps track of basic block code size estimates. |
58 | DenseMap<const BasicBlock *, InstructionCost> NumBBInsts; |
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. |
78 | void analyzeBasicBlock(const BasicBlock *BB, const TargetTransformInfo &TTI, |
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, |
85 | SmallPtrSetImpl<const Value *> &EphValues); |
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, |
90 | SmallPtrSetImpl<const Value *> &EphValues); |
91 | }; |
92 | |
93 | } |
94 | |
95 | #endif |
96 | |