Fix pc_array bounds check to use elements instead of bytes

pc_array_size and kPcArrayMaxSize appear to be measured in elements, not
bytes, so we shouldn't multiply idx by sizeof(uptr) in this bounds
check.  32-bit Chrome was tripping this assertion because it has 64
million coverage points. I don't think it's worth adding a test that has
that many coverage points.

llvm-svn: 292955

1 files changed, 1 insertions, 2 deletions

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_coverage_libcdep.cc b/compiler-rt/lib/sanitizer_common/sanitizer_coverage_libcdep.cc
index ebdee33d7d5..497bdcb88c0 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_coverage_libcdep.cc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_coverage_libcdep.cc
@@ -415,8 +415,7 @@ void CoverageData::Add(uptr pc, u32 *guard) {
   uptr idx = -guard_value - 1;
   if (idx >= atomic_load(&pc_array_index, memory_order_acquire))
     return;  // May happen after fork when pc_array_index becomes 0.
-  CHECK_LT(idx * sizeof(uptr),
-           atomic_load(&pc_array_size, memory_order_acquire));
+  CHECK_LT(idx, atomic_load(&pc_array_size, memory_order_acquire));
   uptr counter = atomic_fetch_add(&coverage_counter, 1, memory_order_relaxed);
   pc_array[idx] = BundlePcAndCounter(pc, counter);
 }