File: macro-complexity.cpp

package info (click to toggle)
llvm-toolchain-14 1%3A14.0.6-16
  • links: PTS, VCS
  • area: main
  • in suites:
  • size: 1,496,368 kB
  • sloc: cpp: 5,593,980; ansic: 986,873; asm: 585,869; python: 184,223; objc: 72,530; lisp: 31,119; f90: 27,793; javascript: 9,780; pascal: 9,762; sh: 9,482; perl: 7,468; ml: 5,432; awk: 3,523; makefile: 2,547; xml: 953; cs: 573; fortran: 567
file content (50 lines) | stat: -rw-r--r-- 2,010 bytes parent folder | download | duplicates (27)
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
// RUN: %clang_analyze_cc1 -std=c++11 -analyzer-checker=alpha.clone.CloneChecker -analyzer-config alpha.clone.CloneChecker:MinimumCloneComplexity=10 -verify %s

// Tests that the complexity value of a macro expansion is about the same as
// the complexity value of a normal function call and the macro body doesn't
// influence the complexity. See the CloneSignature class in CloneDetection.h
// for more information about complexity values of clones.

#define MACRO_FOO(a, b) a > b ? -a * a : -b * b;

// First, manually apply MACRO_FOO and see if the code gets detected as a clone.
// This confirms that with the current configuration the macro body would be
// considered large enough to pass the MinimumCloneComplexity constraint.

int manualMacro(int a, int b) { // expected-warning{{Duplicate code detected}}
  return a > b ? -a * a : -b * b;
}

int manualMacroClone(int a, int b) { // expected-note{{Similar code here}}
  return a > b ? -a * a : -b * b;
}

// Now we actually use the macro to generate the same AST as above. They
// shouldn't be reported because the macros only slightly increase the complexity
// value and the resulting code will never pass the MinimumCloneComplexity
// constraint.

int macro(int a, int b) {
  return MACRO_FOO(a, b);
}

int macroClone(int a, int b) {
  return MACRO_FOO(a, b);
}

// So far we only tested that macros increase the complexity by a lesser amount
// than normal code. We also need to be sure this amount is not zero because
// we otherwise macro code would be 'invisible' for the CloneDetector.
// This tests that it is possible to increase the reach the minimum complexity
// by only using macros. This is only possible if the complexity value is bigger
// than zero.

#define NEG(A) -(A)

int nestedMacros() { // expected-warning{{Duplicate code detected}}
  return NEG(NEG(NEG(NEG(NEG(NEG(NEG(NEG(NEG(NEG(1))))))))));
}

int nestedMacrosClone() { // expected-note{{Similar code here}}
  return NEG(NEG(NEG(NEG(NEG(NEG(NEG(NEG(NEG(NEG(1))))))))));
}