Leland-Takamine

long start = System.currentTimeMillis();
while (true) {
    int n = inputStream.read(buffer, 0, size - bytesRead);
    if (n == -1) {
        long msSinceStart = System.currentTimeMillis() - start;
        if (waitForData && msSinceStart < TIMEOUT) {
            pause();
        } else {
            throw new IOException("Unable to read trace data");
        }

Leland-Takamine

Keybase proof

I hereby claim:

• I am leland-takamine on github.
• I am leland (https://keybase.io/leland) on keybase.
• I have a public key ASDMAfSygt7uW2rNSpxYkmq_InQ_JSR6orQxSQUmwYchIAo

To claim this, I am signing this object:

Leland-Takamine

; TR = thread register
; MR = method register
; data_ptr = temp register
; timestamp = temp register

VisitTraceStart:
    LDR data_ptr, [TR, data_ptr_offset]  ; data_ptr = thread.data_ptr
    CBZ data_ptr, done                   ; if (data_ptr != null)
    MRS timestamp, SYS_CNTVCT_EL0        ;     timestamp = <Generic Timer count>
    STR MR, [data_ptr], +8               ;     *data_ptr++ = method

Leland-Takamine

void Thread::TraceStart(ArtMethod* method) {
  if (LIKELY(tlsPtr_.trace_data_ptr != nullptr)) {
    *tlsPtr_.trace_data_ptr++ = reinterpret_cast<int64_t>(method);
    *tlsPtr_.trace_data_ptr++ = generic_timer_count();
  }
}

void Thread::TraceEnd(ArtMethod* method) {
  if (LIKELY(tlsPtr_.trace_data_ptr != nullptr)) {
    *tlsPtr_.trace_data_ptr++ = 0;

Leland-Takamine

static inline JValue Execute(Thread* self, ...) {
  …
  self->TraceStart(method);
  … // Method execution logic
  self->TraceEnd(method);
  …
}

Leland-Takamine

import org.junit.Test;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.List;

import static org.assertj.core.api.Assertions.assertThat;

/**