Fix audioflinger in integer sanitized builds.
Refactor threadLoop() to avoid unsigned integer overflows
which were causing errors on integer sanitized builds.
Also disable sanitization in fnv1a.
Bug: 30969751
Test: Compiles with and without integer sanitization.
Test: Device boots.
Change-Id: Ia8201e8a8f1d4df2b356ec81003fb07598db4546
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index 1e88ab2..242c9ba 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -3312,9 +3312,13 @@
// 2. threadLoop_mix (significant for heavy mixing, especially
// on low tier processors)
- // it's OK if deltaMs is an overestimate.
- const int32_t deltaMs =
- (lastWriteFinished - previousLastWriteFinished) / 1000000;
+ // it's OK if deltaMs (and deltaNs) is an overestimate.
+ nsecs_t deltaNs;
+ // deltaNs = lastWriteFinished - previousLastWriteFinished;
+ __builtin_sub_overflow(
+ lastWriteFinished,previousLastWriteFinished, &deltaNs);
+ const int32_t deltaMs = deltaNs / 1000000;
+
const int32_t throttleMs = mHalfBufferMs - deltaMs;
if ((signed)mHalfBufferMs >= throttleMs && throttleMs > 0) {
usleep(throttleMs * 1000);
diff --git a/services/audioflinger/TypedLogger.h b/services/audioflinger/TypedLogger.h
index cae74b1..38c3c02 100644
--- a/services/audioflinger/TypedLogger.h
+++ b/services/audioflinger/TypedLogger.h
@@ -64,7 +64,8 @@
}
template <typename T, size_t n>
-constexpr T fnv1a(const char (&file)[n], int i = n - 1) {
+__attribute__((no_sanitize("unsigned-integer-overflow")))
+constexpr T fnv1a(const char (&file)[n], ssize_t i = (ssize_t)n - 1) {
return i == -1 ? offset_basis<T>() : (fnv1a<T>(file, i - 1) ^ file[i]) * FNV_prime<T>();
}