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https://github.com/revng/revng
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Alessandro Di Federico
540b87e2ff
InlineHelpers often inlines functions that contain a switch on an argument that is constant on the call site. Specifically, this is true for the `cc_compute_c` and `cc_compute_all` helpers of x86 architectures. The LLVM inliner, in such situations, is smart and inlines a reduced amount of code, significantly reducing the maximum size of the modules we work with. However, before this commit, we couldn't capture this fact due to `newpc` preventing constant propagation of the values of CSV set in an instruction into their usage in the next instruction. Running `PromoteCSV` before `InlineHelpers`, along with `mem2reg` enables us to capture this behavior effectively.
Purpose
revng is a static binary translator. Given a input ELF binary for one of the supported architectures (currently i386, x86-64, MIPS, ARM, AArch64 and s390x) it will analyze it and emit an equivalent LLVM IR. To do so, revng employs the QEMU intermediate representation (a series of TCG instructions) and then translates them to LLVM IR.
How to build
revng employs CMake as a build system.
In order to build revng, use orchestra and make sure you're building revng from source.
You can install as follows:
orc install revng
Remember to enter an orc shell to run revng:
orc shell
revng --help
You can run the test suite as follows:
orc install --test revng
Example run
The simplest possible example consists in the following:
# Install revng
orc install revng
# Install the ARM toolchain
orc install toolchain/arm/gcc
# Enter in the build directory
orc shell -c revng
# Build
ninja
# Create hello world program
cat > hello.c <<EOF
#include <stdio.h>
int main(int argc, char *argv[]) {
printf("Hello, world!\n");
}
EOF
# Compile
armv7a-hardfloat-linux-uclibceabi-gcc \
-Wl,-Ttext-segment=0x20000 \
-static hello.c \
-o hello.arm
# Translate
./bin/revng translate hello.arm
chmod +x hello.arm.translated
# Run translated version
./hello.arm.translated
# Hello, world!