xref: /llvm-project/llvm/unittests/Transforms/Utils/CodeExtractorTest.cpp (revision 2946cd701067404b99c39fb29dc9c74bd7193eb3)
1 //===- CodeExtractor.cpp - Unit tests for CodeExtractor -------------------===//
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 #include "llvm/Transforms/Utils/CodeExtractor.h"
10 #include "llvm/AsmParser/Parser.h"
11 #include "llvm/IR/BasicBlock.h"
12 #include "llvm/IR/Dominators.h"
13 #include "llvm/IR/Instructions.h"
14 #include "llvm/IR/LLVMContext.h"
15 #include "llvm/IR/Module.h"
16 #include "llvm/IR/Verifier.h"
17 #include "llvm/IRReader/IRReader.h"
18 #include "llvm/Support/SourceMgr.h"
19 #include "gtest/gtest.h"
20 
21 using namespace llvm;
22 
23 namespace {
24 BasicBlock *getBlockByName(Function *F, StringRef name) {
25   for (auto &BB : *F)
26     if (BB.getName() == name)
27       return &BB;
28   return nullptr;
29 }
30 
31 TEST(CodeExtractor, ExitStub) {
32   LLVMContext Ctx;
33   SMDiagnostic Err;
34   std::unique_ptr<Module> M(parseAssemblyString(R"invalid(
35     define i32 @foo(i32 %x, i32 %y, i32 %z) {
36     header:
37       %0 = icmp ugt i32 %x, %y
38       br i1 %0, label %body1, label %body2
39 
40     body1:
41       %1 = add i32 %z, 2
42       br label %notExtracted
43 
44     body2:
45       %2 = mul i32 %z, 7
46       br label %notExtracted
47 
48     notExtracted:
49       %3 = phi i32 [ %1, %body1 ], [ %2, %body2 ]
50       %4 = add i32 %3, %x
51       ret i32 %4
52     }
53   )invalid",
54                                                 Err, Ctx));
55 
56   Function *Func = M->getFunction("foo");
57   SmallVector<BasicBlock *, 3> Candidates{ getBlockByName(Func, "header"),
58                                            getBlockByName(Func, "body1"),
59                                            getBlockByName(Func, "body2") };
60 
61   DominatorTree DT(*Func);
62   CodeExtractor CE(Candidates, &DT);
63   EXPECT_TRUE(CE.isEligible());
64 
65   Function *Outlined = CE.extractCodeRegion();
66   EXPECT_TRUE(Outlined);
67   BasicBlock *Exit = getBlockByName(Func, "notExtracted");
68   BasicBlock *ExitSplit = getBlockByName(Outlined, "notExtracted.split");
69   // Ensure that PHI in exit block has only one incoming value (from code
70   // replacer block).
71   EXPECT_TRUE(Exit && cast<PHINode>(Exit->front()).getNumIncomingValues() == 1);
72   // Ensure that there is a PHI in outlined function with 2 incoming values.
73   EXPECT_TRUE(ExitSplit &&
74               cast<PHINode>(ExitSplit->front()).getNumIncomingValues() == 2);
75   EXPECT_FALSE(verifyFunction(*Outlined));
76   EXPECT_FALSE(verifyFunction(*Func));
77 }
78 
79 TEST(CodeExtractor, ExitPHIOnePredFromRegion) {
80   LLVMContext Ctx;
81   SMDiagnostic Err;
82   std::unique_ptr<Module> M(parseAssemblyString(R"invalid(
83     define i32 @foo() {
84     header:
85       br i1 undef, label %extracted1, label %pred
86 
87     pred:
88       br i1 undef, label %exit1, label %exit2
89 
90     extracted1:
91       br i1 undef, label %extracted2, label %exit1
92 
93     extracted2:
94       br label %exit2
95 
96     exit1:
97       %0 = phi i32 [ 1, %extracted1 ], [ 2, %pred ]
98       ret i32 %0
99 
100     exit2:
101       %1 = phi i32 [ 3, %extracted2 ], [ 4, %pred ]
102       ret i32 %1
103     }
104   )invalid", Err, Ctx));
105 
106   Function *Func = M->getFunction("foo");
107   SmallVector<BasicBlock *, 2> ExtractedBlocks{
108     getBlockByName(Func, "extracted1"),
109     getBlockByName(Func, "extracted2")
110   };
111 
112   DominatorTree DT(*Func);
113   CodeExtractor CE(ExtractedBlocks, &DT);
114   EXPECT_TRUE(CE.isEligible());
115 
116   Function *Outlined = CE.extractCodeRegion();
117   EXPECT_TRUE(Outlined);
118   BasicBlock *Exit1 = getBlockByName(Func, "exit1");
119   BasicBlock *Exit2 = getBlockByName(Func, "exit2");
120   // Ensure that PHIs in exits are not splitted (since that they have only one
121   // incoming value from extracted region).
122   EXPECT_TRUE(Exit1 &&
123           cast<PHINode>(Exit1->front()).getNumIncomingValues() == 2);
124   EXPECT_TRUE(Exit2 &&
125           cast<PHINode>(Exit2->front()).getNumIncomingValues() == 2);
126   EXPECT_FALSE(verifyFunction(*Outlined));
127   EXPECT_FALSE(verifyFunction(*Func));
128 }
129 
130 TEST(CodeExtractor, StoreOutputInvokeResultAfterEHPad) {
131   LLVMContext Ctx;
132   SMDiagnostic Err;
133   std::unique_ptr<Module> M(parseAssemblyString(R"invalid(
134     declare i8 @hoge()
135 
136     define i32 @foo() personality i8* null {
137       entry:
138         %call = invoke i8 @hoge()
139                 to label %invoke.cont unwind label %lpad
140 
141       invoke.cont:                                      ; preds = %entry
142         unreachable
143 
144       lpad:                                             ; preds = %entry
145         %0 = landingpad { i8*, i32 }
146                 catch i8* null
147         br i1 undef, label %catch, label %finally.catchall
148 
149       catch:                                            ; preds = %lpad
150         %call2 = invoke i8 @hoge()
151                 to label %invoke.cont2 unwind label %lpad2
152 
153       invoke.cont2:                                    ; preds = %catch
154         %call3 = invoke i8 @hoge()
155                 to label %invoke.cont3 unwind label %lpad2
156 
157       invoke.cont3:                                    ; preds = %invoke.cont2
158         unreachable
159 
160       lpad2:                                           ; preds = %invoke.cont2, %catch
161         %ex.1 = phi i8* [ undef, %invoke.cont2 ], [ null, %catch ]
162         %1 = landingpad { i8*, i32 }
163                 catch i8* null
164         br label %finally.catchall
165 
166       finally.catchall:                                 ; preds = %lpad33, %lpad
167         %ex.2 = phi i8* [ %ex.1, %lpad2 ], [ null, %lpad ]
168         unreachable
169     }
170   )invalid", Err, Ctx));
171 
172 	if (!M) {
173     Err.print("unit", errs());
174     exit(1);
175   }
176 
177   Function *Func = M->getFunction("foo");
178   EXPECT_FALSE(verifyFunction(*Func, &errs()));
179 
180   SmallVector<BasicBlock *, 2> ExtractedBlocks{
181     getBlockByName(Func, "catch"),
182     getBlockByName(Func, "invoke.cont2"),
183     getBlockByName(Func, "invoke.cont3"),
184     getBlockByName(Func, "lpad2")
185   };
186 
187   DominatorTree DT(*Func);
188   CodeExtractor CE(ExtractedBlocks, &DT);
189   EXPECT_TRUE(CE.isEligible());
190 
191   Function *Outlined = CE.extractCodeRegion();
192   EXPECT_TRUE(Outlined);
193   EXPECT_FALSE(verifyFunction(*Outlined, &errs()));
194   EXPECT_FALSE(verifyFunction(*Func, &errs()));
195 }
196 
197 } // end anonymous namespace
198