Bisection Bug Search

Bisection Bug Search is a tool for finding compiler optimizations bugs. It accepts a program which exposes a bug by producing incorrect output and expected output for the program. It then attempts to narrow down the issue to a single method and optimization pass under the assumption that interpreter is correct.

Given methods in order M0..Mn finds smallest i such that compiling Mi and interpreting all other methods produces incorrect output. Then, given ordered optimization passes P0..Pl, finds smallest j such that compiling Mi with passes P0..Pj-1 produces expected output and compiling Mi with passes P0..Pj produces incorrect output. Prints Mi and Pj.

How to run Bisection Bug Search

bisection_search.py [-h] -cp CLASSPATH
                    [--expected-output EXPECTED_OUTPUT] [--device]
                    [--lib LIB] [--64]
                    [--dalvikvm-option [OPTION [OPTION ...]]]
                    [--arg [TEST_ARGS [TEST_ARGS ...]]] [--image IMAGE]
                    [--verbose]
                    classname

positional arguments:
  classname             name of class to run

optional arguments:
  -h, --help            show this help message and exit
  -cp CLASSPATH, --classpath CLASSPATH
                        classpath
  --expected-output EXPECTED_OUTPUT
                        file containing expected output
  --device              run on device
  --lib LIB             lib to use, default: libart.so
  --64                  x64 mode
  --dalvikvm-option [OPTION [OPTION ...]]
                        additional dalvikvm option
  --arg [TEST_ARGS [TEST_ARGS ...]]
                        argument to pass to program
  --image IMAGE         path to image
  --verbose             enable verbose output