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
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
/*========================== begin_copyright_notice ============================
Copyright (C) 2022 Intel Corporation
SPDX-License-Identifier: MIT
============================= end_copyright_notice ===========================*/
#include "Compiler/CISACodeGen/CastToGASAnalysis.h"
#include "Compiler/CodeGenPublic.h"
#include "Compiler/CodeGenPublicEnums.h"
#include "Compiler/IGCPassSupport.h"
#include "Probe/Assertion.h"
#include "llvmWrapper/Analysis/CallGraph.h"
#include "common/LLVMWarningsPush.hpp"
#include <llvm/Pass.h>
#include <llvm/IR/Function.h>
#include <llvm/IR/Instructions.h>
#include <llvm/IR/InstIterator.h>
#include <llvm/Analysis/CallGraph.h>
#include "common/LLVMWarningsPop.hpp"
using namespace llvm;
using namespace IGC;
char CastToGASWrapperPass::ID = 0;
#define PASS_FLAG "generic-pointer-analysis"
#define PASS_DESCRIPTION "Analyze generic pointer usage"
#define PASS_CFG_ONLY false
#define PASS_ANALYSIS true
IGC_INITIALIZE_PASS_BEGIN(CastToGASWrapperPass, PASS_FLAG, PASS_DESCRIPTION, PASS_CFG_ONLY, PASS_ANALYSIS)
INITIALIZE_PASS_DEPENDENCY(CallGraphWrapperPass)
IGC_INITIALIZE_PASS_END(CastToGASWrapperPass, PASS_FLAG, PASS_DESCRIPTION, PASS_CFG_ONLY, PASS_ANALYSIS)
void CastToGASWrapperPass::getAllFuncsAccessibleFromKernel(const Function* F, CallGraph& CG, SmallPtrSetImpl<const Function*>& funcs, bool& disruptAnalysis) const
{
IGC_ASSERT(F->getCallingConv() == CallingConv::SPIR_KERNEL);
disruptAnalysis = false;
SmallVector<const Function*, 16> worklist;
worklist.push_back(F);
while (!worklist.empty())
{
const Function* F = worklist.back();
worklist.pop_back();
CallGraphNode& N = *CG[F];
for (IGCLLVM::CallRecord CE : N)
{
const Function* child = CE.second->getFunction();
if (!child)
{
if (CallBase* CB = dyn_cast_or_null<CallBase>(CE.first.getValue()))
{
if (CB->isIndirectCall())
{
// Continue gathering all functions accessible from kernel "F" even if disruption
// happens to find out what functions need additional control flow for GAS accesses
disruptAnalysis = true;
}
}
continue;
}
if (child->isDeclaration()) continue;
const bool notVisited = funcs.insert(child).second;
if (notVisited)
{
worklist.push_back(child);
}
}
}
}
unsigned CastToGASWrapperPass::hasCastsToGeneric(const Function* F)
{
if (castInfoCache.count(F))
return castInfoCache[F];
unsigned castInfo = 0;
for (auto& I : instructions(F))
{
if (castInfo == (HasPrivateToGenericCast | HasLocalToGenericCast)) break;
if (auto* ASC = dyn_cast<AddrSpaceCastInst>(&I))
{
if (ASC->getDestAddressSpace() != ADDRESS_SPACE_GENERIC)
continue;
unsigned AS = ASC->getSrcAddressSpace();
if (AS == ADDRESS_SPACE_PRIVATE)
castInfo |= HasPrivateToGenericCast;
else if (AS == ADDRESS_SPACE_LOCAL)
castInfo |= HasLocalToGenericCast;
}
}
castInfoCache[F] = castInfo;
return castInfo;
}
void CastToGASWrapperPass::setInfoForGroup(
llvm::SmallPtrSetImpl<const llvm::Function*>& functionsGroup,
unsigned castInfo)
{
for (auto F : functionsGroup)
{
auto E = GI.FunctionMap.find(F);
if (E != GI.FunctionMap.end())
{
// If a function already exists in the map, it means that it is called by more than one
// kernel. Existing element represents a result of an analysis processed on another
// kernel call graph. Below code makes an OR operation on previous and current analysis
// results to take both into account.
GI.FunctionMap[F] = E->second | castInfo;
continue;
}
GI.FunctionMap[F] = castInfo;
}
}
bool CastToGASWrapperPass::runOnModule(Module& M)
{
m_ctx = getAnalysis<CodeGenContextWrapper>().getCodeGenContext();
GI.noLocalToGenericOptionEnabled = m_ctx->noLocalToGenericOptionEnabled();
GI.allocatePrivateAsGlobalBuffer = m_ctx->allocatePrivateAsGlobalBuffer();
if (GI.noLocalToGenericOptionEnabled && GI.allocatePrivateAsGlobalBuffer)
return false;
castInfoCache.clear();
CallGraph& CG = getAnalysis<CallGraphWrapperPass>().getCallGraph();
for (auto& F : M.functions()) {
if (F.getCallingConv() != llvm::CallingConv::SPIR_KERNEL)
continue;
bool disruptAnalysis = false;
SmallPtrSet<const Function*, 32> functions;
getAllFuncsAccessibleFromKernel(&F, CG, functions, disruptAnalysis);
functions.insert(&F);
if (disruptAnalysis)
{
setInfoForGroup(functions, HasPrivateToGenericCast | HasLocalToGenericCast);
continue;
}
unsigned info = 0;
for (auto F : functions)
{
info |= hasCastsToGeneric(F);
// early exit if private and local casts have been found
if (info == (HasPrivateToGenericCast | HasLocalToGenericCast))
break;
}
setInfoForGroup(functions, info);
}
return false;
}
|
