compiler-rt/test/xray/TestCases/Posix/coverage-sample.cpp

   1 // Check that we can patch and unpatch specific function ids.
   2 //
   3 // RUN: %clangxx_xray -std=c++11 %s -o %t
   4 // RUN: XRAY_OPTIONS="patch_premain=false" %run %t | FileCheck %s
   5 // RUN: %clangxx_xray -fno-xray-function-index -std=c++11 %s -o %t
   6 // RUN: XRAY_OPTIONS="patch_premain=false" %run %t | FileCheck %s
   7
   8 // UNSUPPORTED: target-is-mips64,target-is-mips64el
   9
  10 #include "xray/xray_interface.h"
  11
  12 #include <set>
  13 #include <cstdio>
  14 #include <cassert>
  15
  16 std::set<int32_t> function_ids;
  17
  18 [[clang::xray_never_instrument]] void coverage_handler(int32_t fid,
  19                                                        XRayEntryType) {
  20   thread_local bool patching = false;
  21   if (patching) return;
  22   patching = true;
  23   function_ids.insert(fid);
  24   __xray_unpatch_function(fid);
  25   patching = false;
  26 }
  27
  28 [[clang::xray_always_instrument]] void baz() {
  29   // do nothing!
  30 }
  31
  32 [[clang::xray_always_instrument]] void bar() {
  33   baz();
  34 }
  35
  36 [[clang::xray_always_instrument]] void foo() {
  37   bar();
  38 }
  39
  40 [[clang::xray_always_instrument]] int main(int argc, char *argv[]) {
  41   __xray_set_handler(coverage_handler);
  42   assert(__xray_patch() == XRayPatchingStatus::SUCCESS);
  43   foo();
  44   assert(__xray_unpatch() == XRayPatchingStatus::SUCCESS);
  45
  46   // print out the function_ids.
  47   printf("first pass.\n");
  48   for (const auto id : function_ids)
  49     printf("patched: %d\n", id);
  50
  51   // CHECK-LABEL: first pass.
  52   // CHECK-DAG: patched: [[F1:.*]]
  53   // CHECK-DAG: patched: [[F2:.*]]
  54   // CHECK-DAG: patched: [[F3:.*]]
  55
  56   // make a copy of the function_ids, then patch them later.
  57   auto called_fns = function_ids;
  58
  59   // clear the function_ids.
  60   function_ids.clear();
  61
  62   // patch the functions we've called before.
  63   for (const auto id : called_fns)
  64     assert(__xray_patch_function(id) == XRayPatchingStatus::SUCCESS);
  65
  66   // then call them again.
  67   foo();
  68   assert(__xray_unpatch() == XRayPatchingStatus::SUCCESS);
  69
  70   // confirm that we've seen the same functions again.
  71   printf("second pass.\n");
  72   for (const auto id : function_ids)
  73     printf("patched: %d\n", id);
  74   // CHECK-LABEL: second pass.
  75   // CHECK-DAG: patched: [[F1]]
  76   // CHECK-DAG: patched: [[F2]]
  77   // CHECK-DAG: patched: [[F3]]
  78
  79   // Now we want to make sure that if we unpatch one, that we're only going to
  80   // see two calls of the coverage_handler.
  81   function_ids.clear();
  82   assert(__xray_patch() == XRayPatchingStatus::SUCCESS);
  83   assert(__xray_unpatch_function(1) == XRayPatchingStatus::SUCCESS);
  84   foo();
  85   assert(__xray_unpatch() == XRayPatchingStatus::SUCCESS);
  86
  87   // confirm that we don't see function id one called anymore.
  88   printf("missing 1.\n");
  89   for (const auto id : function_ids)
  90     printf("patched: %d\n", id);
  91   // CHECK-LABEL: missing 1.
  92   // CHECK-NOT: patched: 1
  93 }