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
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
//===- IVDescriptorsTest.cpp - IVDescriptors unit tests -------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/IVDescriptors.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/AsmParser/Parser.h"
#include "llvm/IR/Dominators.h"
#include "llvm/Support/SourceMgr.h"
#include "gtest/gtest.h"
using namespace llvm;
/// Build the loop info and scalar evolution for the function and run the Test.
static void runWithLoopInfoAndSE(
Module &M, StringRef FuncName,
function_ref<void(Function &F, LoopInfo &LI, ScalarEvolution &SE)> Test) {
auto *F = M.getFunction(FuncName);
ASSERT_NE(F, nullptr) << "Could not find " << FuncName;
TargetLibraryInfoImpl TLII;
TargetLibraryInfo TLI(TLII);
AssumptionCache AC(*F);
DominatorTree DT(*F);
LoopInfo LI(DT);
ScalarEvolution SE(*F, TLI, AC, DT, LI);
Test(*F, LI, SE);
}
static std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) {
SMDiagnostic Err;
std::unique_ptr<Module> Mod = parseAssemblyString(IR, Err, C);
if (!Mod)
Err.print("IVDescriptorsTests", errs());
return Mod;
}
// This tests that IVDescriptors can obtain the induction binary operator for
// integer induction variables. And getExactFPMathInst() correctly return the
// expected behavior, i.e. no FMF algebra.
TEST(IVDescriptorsTest, LoopWithSingleLatch) {
// Parse the module.
LLVMContext Context;
std::unique_ptr<Module> M = parseIR(
Context,
R"(define void @foo(i32* %A, i32 %ub) {
entry:
br label %for.body
for.body:
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%idxprom = sext i32 %i to i64
%arrayidx = getelementptr inbounds i32, i32* %A, i64 %idxprom
store i32 %i, i32* %arrayidx, align 4
%inc = add nsw i32 %i, 1
%cmp = icmp slt i32 %inc, %ub
br i1 %cmp, label %for.body, label %for.exit
for.exit:
br label %for.end
for.end:
ret void
})"
);
runWithLoopInfoAndSE(
*M, "foo", [&](Function &F, LoopInfo &LI, ScalarEvolution &SE) {
Function::iterator FI = F.begin();
// First basic block is entry - skip it.
BasicBlock *Header = &*(++FI);
assert(Header->getName() == "for.body");
Loop *L = LI.getLoopFor(Header);
EXPECT_NE(L, nullptr);
PHINode *Inst_i = dyn_cast<PHINode>(&Header->front());
assert(Inst_i->getName() == "i");
InductionDescriptor IndDesc;
bool IsInductionPHI =
InductionDescriptor::isInductionPHI(Inst_i, L, &SE, IndDesc);
EXPECT_TRUE(IsInductionPHI);
Instruction *Inst_inc = nullptr;
BasicBlock::iterator BBI = Header->begin();
do {
if ((&*BBI)->getName() == "inc")
Inst_inc = &*BBI;
++BBI;
} while (!Inst_inc);
assert(Inst_inc->getName() == "inc");
EXPECT_EQ(IndDesc.getInductionBinOp(), Inst_inc);
EXPECT_EQ(IndDesc.getExactFPMathInst(), nullptr);
});
}
TEST(IVDescriptorsTest, LoopWithScalableTypes) {
// Parse the module.
LLVMContext Context;
std::unique_ptr<Module> M =
parseIR(Context,
R"(define void @foo(<vscale x 4 x float>* %ptr) {
entry:
br label %for.body
for.body:
%lsr.iv1 = phi <vscale x 4 x float>* [ %0, %for.body ], [ %ptr, %entry ]
%j.0117 = phi i64 [ %inc, %for.body ], [ 0, %entry ]
%lsr.iv12 = bitcast <vscale x 4 x float>* %lsr.iv1 to i8*
%inc = add nuw nsw i64 %j.0117, 1
%uglygep = getelementptr i8, i8* %lsr.iv12, i64 4
%0 = bitcast i8* %uglygep to <vscale x 4 x float>*
%cmp = icmp ne i64 %inc, 1024
br i1 %cmp, label %for.body, label %end
end:
ret void
})");
runWithLoopInfoAndSE(
*M, "foo", [&](Function &F, LoopInfo &LI, ScalarEvolution &SE) {
Function::iterator FI = F.begin();
// First basic block is entry - skip it.
BasicBlock *Header = &*(++FI);
assert(Header->getName() == "for.body");
Loop *L = LI.getLoopFor(Header);
EXPECT_NE(L, nullptr);
PHINode *Inst_iv = dyn_cast<PHINode>(&Header->front());
assert(Inst_iv->getName() == "lsr.iv1");
InductionDescriptor IndDesc;
bool IsInductionPHI =
InductionDescriptor::isInductionPHI(Inst_iv, L, &SE, IndDesc);
EXPECT_FALSE(IsInductionPHI);
});
}
// Depending on how SCEV deals with ptrtoint cast, the step of a phi could be
// a pointer, and InductionDescriptor used to fail with an assertion.
// So just check that it doesn't assert.
TEST(IVDescriptorsTest, LoopWithPtrToInt) {
// Parse the module.
LLVMContext Context;
std::unique_ptr<Module> M = parseIR(Context, R"(
target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
target triple = "thumbv6m-arm-none-eabi"
declare void @widget()
declare void @wobble(i32)
define void @barney(i8* %arg, i8* %arg18, i32 %arg19) {
bb:
%tmp = ptrtoint i8* %arg to i32
%tmp20 = ptrtoint i8* %arg18 to i32
%tmp21 = or i32 %tmp20, %tmp
%tmp22 = and i32 %tmp21, 3
%tmp23 = icmp eq i32 %tmp22, 0
br i1 %tmp23, label %bb24, label %bb25
bb24:
tail call void @widget()
br label %bb34
bb25:
%tmp26 = sub i32 %tmp, %tmp20
%tmp27 = icmp ult i32 %tmp26, %arg19
br i1 %tmp27, label %bb28, label %bb34
bb28:
br label %bb29
bb29:
%tmp30 = phi i32 [ %tmp31, %bb29 ], [ %arg19, %bb28 ]
tail call void @wobble(i32 %tmp26)
%tmp31 = sub i32 %tmp30, %tmp26
%tmp32 = icmp ugt i32 %tmp31, %tmp26
br i1 %tmp32, label %bb29, label %bb33
bb33:
br label %bb34
bb34:
ret void
})");
runWithLoopInfoAndSE(
*M, "barney", [&](Function &F, LoopInfo &LI, ScalarEvolution &SE) {
Function::iterator FI = F.begin();
// First basic block is entry - skip it.
BasicBlock *Header = &*(++(++(++(++FI))));
assert(Header->getName() == "bb29");
Loop *L = LI.getLoopFor(Header);
EXPECT_NE(L, nullptr);
PHINode *Inst_i = dyn_cast<PHINode>(&Header->front());
assert(Inst_i->getName() == "tmp30");
InductionDescriptor IndDesc;
bool IsInductionPHI =
InductionDescriptor::isInductionPHI(Inst_i, L, &SE, IndDesc);
EXPECT_TRUE(IsInductionPHI);
});
}
|
