1 //: Automatically aggregate functions starting with 'test-' into a test suite
 2 //: called 'run-tests'. Running this function will run all tests.
 3 //:
 4 //: This is actually SubX's first (trivial) compiler. We generate all the code
 5 //: needed for the 'run-tests' function.
 6 //:
 7 //: By convention, temporary functions needed by tests will start with
 8 //: '_test-'.
 9 
10 //: We don't rely on any transforms running in previous layers, but this layer
11 //: knows about labels and will emit labels for previous layers to transform.
12 :(after "Begin Transforms")
13 // Begin Level-4 Transforms
14 Transform.push_back(create_test_function);
15 // End Level-4 Transforms
16 
17 :(scenario run_test)
18 % Reg[ESP].u = 0x100;
19 == 0x1
20 main:
21   e8/call run-tests/disp32  # 5 bytes
22   f4/halt                   # 1 byte
23 
24 test-foo:  # offset 7
25   01 d8  # just some unique instruction: add EBX to EAX
26   c3/return
27 
28 # check that code in test-foo ran (implicitly called by run-tests)
29 +run: inst: 0x00000007
30 
31 :(code)
32 void create_test_function(program& p) {
33   if (p.segments.empty()) return;
34   segment& code = p.segments.at(0);
35   trace(99, "transform") << "-- create 'run-tests'" << end();
36   vector<line> new_insts;
37   for (int i = 0;  i < SIZE(code.lines);  ++i) {
38     line& inst = code.lines.at(i);
39     for (int j = 0;  j < SIZE(inst.words);  ++j) {
40       const word& curr = inst.words.at(j);
41       if (*curr.data.rbegin() != ':') continue;  // not a label
42       if (!starts_with(curr.data, "test-")) continue;
43       string fn = drop_last(curr.data);
44       new_insts.push_back(call(fn));
45     }
46   }
47   if (new_insts.empty()) return;  // no tests found
48   code.lines.push_back(label("run-tests"));
49   code.lines.insert(code.lines.end(), new_insts.begin(), new_insts.end());
50   code.lines.push_back(ret());
51 }
52 
53 string to_string(const segment& s) {
54   ostringstream out;
55   for (int i = 0;  i < SIZE(s.lines);  ++i) {
56     const line& l = s.lines.at(i);
57     for (int j = 0;  j < SIZE(l.words);  ++j) {
58       if (j > 0) out << ' ';
59       out << to_string(l.words.at(j));
60     }
61     out << '\n';
62   }
63   return out.str();
64 }
65 
66 line call(string s) {
67   line result;
68   result.words.push_back(call());
69   result.words.push_back(disp32(s));
70   return result;
71 }
72 
73 word call() {
74   word result;
75   result.data = "e8";
76   result.metadata.push_back("call");
77   return result;
78 }
79 
80 word disp32(string s) {
81   word result;
82   result.data = s;
83   result.metadata.push_back("disp32");
84   return result;
85 }
86 
87 line ret() {
88   line result;
89   result.words.push_back(word());
90   result.words.back().data = "c3";
91   result.words.back().metadata.push_back("return");
92   return result;
93 }