1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
//===- llvm/CodeGen/PseudoProbePrinter.cpp - Pseudo Probe Emission -------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains support for writing pseudo probe info into asm files.
//
//===----------------------------------------------------------------------===//
#include "PseudoProbePrinter.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/PseudoProbe.h"
#include "llvm/MC/MCPseudoProbe.h"
#include "llvm/MC/MCStreamer.h"
#ifndef NDEBUG
#include "llvm/IR/Module.h"
#include "llvm/Support/WithColor.h"
#endif
using namespace llvm;
void PseudoProbeHandler::emitPseudoProbe(uint64_t Guid, uint64_t Index,
uint64_t Type, uint64_t Attr,
const DILocation *DebugLoc) {
// Gather all the inlined-at nodes.
// When it's done ReversedInlineStack looks like ([66, B], [88, A])
// which means, Function A inlines function B at calliste with a probe id 88,
// and B inlines C at probe 66 where C is represented by Guid.
SmallVector<InlineSite, 8> ReversedInlineStack;
auto *InlinedAt = DebugLoc ? DebugLoc->getInlinedAt() : nullptr;
while (InlinedAt) {
auto Name = InlinedAt->getSubprogramLinkageName();
// Use caching to avoid redundant md5 computation for build speed.
uint64_t &CallerGuid = NameGuidMap[Name];
if (!CallerGuid)
CallerGuid = Function::getGUIDAssumingExternalLinkage(Name);
#ifndef NDEBUG
verifyGuidExistenceInDesc(CallerGuid, Name);
#endif
uint64_t CallerProbeId = PseudoProbeDwarfDiscriminator::extractProbeIndex(
InlinedAt->getDiscriminator());
ReversedInlineStack.emplace_back(CallerGuid, CallerProbeId);
InlinedAt = InlinedAt->getInlinedAt();
}
uint64_t Discriminator = 0;
// For now only block probes have FS discriminators. See
// MIRFSDiscriminator.cpp for more details.
if (EnableFSDiscriminator && DebugLoc &&
(Type == (uint64_t)PseudoProbeType::Block))
Discriminator = DebugLoc->getDiscriminator();
assert((EnableFSDiscriminator || Discriminator == 0) &&
"Discriminator should not be set in non-FSAFDO mode");
SmallVector<InlineSite, 8> InlineStack(llvm::reverse(ReversedInlineStack));
Asm->OutStreamer->emitPseudoProbe(Guid, Index, Type, Attr, Discriminator,
InlineStack, Asm->CurrentFnSym);
#ifndef NDEBUG
verifyGuidExistenceInDesc(
Guid, DebugLoc ? DebugLoc->getSubprogramLinkageName() : "");
#endif
}
#ifndef NDEBUG
void PseudoProbeHandler::verifyGuidExistenceInDesc(uint64_t Guid,
StringRef FuncName) {
NamedMDNode *Desc = Asm->MF->getFunction().getParent()->getNamedMetadata(
PseudoProbeDescMetadataName);
assert(Desc && "pseudo probe does not exist");
// Keep DescGuidSet up to date.
for (size_t I = DescGuidSet.size(), E = Desc->getNumOperands(); I != E; ++I) {
const auto *MD = cast<MDNode>(Desc->getOperand(I));
auto *ID = mdconst::extract<ConstantInt>(MD->getOperand(0));
DescGuidSet.insert(ID->getZExtValue());
}
if (!DescGuidSet.contains(Guid))
WithColor::warning() << "Guid:" << Guid << " Name:" << FuncName
<< " does not exist in pseudo probe desc\n";
}
#endif
|
