Name: Ounan Ding
Email: oding001@ucr.edu
ID: 861194909
Build and test instructions
1. Be sure to include clang/llvm executables in your PATH environment variable.
During the build process
I will use clang++ to generate a LLVM module `utility.bc`
from `support/utility.cpp`
and link it with the instrumented module using llvm-link.
A function is inserted into the testee program
and it will pass the control to our `utility.cpp`.
In this support module `utility.cpp`
I put code to output profiling results.
In this way I can avoid composing many function calls/array indexing
in LLVM Pass API, which is tedious.
2. Run `buildAndTest.sh <test filename>` to perform the build and test.
The first part is the analysis result.
It will output the predecessors, dominator sets, and loops.
All of these informations are printed for each function *SEPARATELY*.
The second part(after the "END OF ANALYSIS" line)
shows the profiling result.
It will output the basic block/edge/loop profiling result.
3. To dump basic blocks
I added a command line `-dumpbb` to our Pass.
You can switch this option by passing it to opt.
By default it is turned off.
4. Some extra notes on this submission
4.1 Loop names
I assign a unique name for each loops.
And I will use this name to identify each loop in the profiling report.
You can find these loop names(e.g. "loop0") in the analysis report.
4.2 Edges across the functions
Some edges in CFG are across the function boundary.
Sometimes the basic blocks may be given a same name, such as "entry".
This would cause some confusion when you see "entry -> entry"
(This is actually an edge from the "entry" block of the main function
to the "entry" block of the function_1 function in our first test sample).
So I assign an ID for each basic block.
You can find this ID at the start of profiling result.
-------------------------------------------------------------------------------
Running the pass and the generated IR
$ ./buildAndTest.sh sai # to test support/sai.c
# Above script does the following:
$ clang -emit-llvm support/sai.c -c -o support/sai.bc
$ make clean && make && ~/Workspace/llvm/Debug+Asserts/bin/opt -load ../../../Debug+Asserts/lib/BasicBlocksDemo.dylib -bbdemo sai.bc -S -o support/sai.ll
$ ~/Workspace/llvm/Debug+Asserts/bin/llvm-as support/sai.ll -o support/sai.bb.bc
$ ~/Workspace/llvm/Debug+Asserts/bin/lli support/sai.bb.bc
# tar -czf BasicBlocksDemo.tar.gz --exclude .git* --exclude *Store --exclude Debug* BasicBlocksDemo
# tar -tvf BasicBlocksDemo.tar.gz