Skip to content

QEMU_RUN.md

Latest commit

 

History

History
82 lines (61 loc) · 2.07 KB

QEMU_RUN.md

File metadata and controls

82 lines (61 loc) · 2.07 KB
Raw

Running Compiler Output in QEMU

The compiler now supports running compiled executables in QEMU user mode emulation.

Quick Start

Option 1: Use the compiler's --qemu flag

python3 compiler.py test_simd_2.c -o test_simd_2 --qemu

This will:

  1. Compile the C file to assembly
  2. Assemble and link it
  3. Automatically run it in QEMU user mode

Option 2: Use the build script with QEMU

./build.sh output.asm output qemu

Option 3: Use the standalone QEMU runner

# First compile and build normally
python3 compiler.py test_simd_2.c -o test_simd_2
# Then run in QEMU
./run_qemu.sh test_simd_2

Installation

Install QEMU User Mode (Recommended)

On Debian/Ubuntu:

sudo apt-get install qemu-user

On RHEL/CentOS/Fedora:

sudo yum install qemu-user
# or
sudo dnf install qemu-user

Verify Installation

qemu-x86_64 --version

What Changed

  1. Fixed _start function: Now properly calls main() and exits with the return code
  2. Added exit system call: Programs now properly terminate using sys_exit (syscall 60)
  3. QEMU integration: Added --qemu flag to compiler and helper scripts

How It Works

The compiler generates ELF64 executables that can run in:

  • Native mode: Directly on your Linux system (./output)
  • QEMU user mode: Emulated execution (qemu-x86_64 output)

QEMU user mode is useful for:

  • Testing on different architectures
  • Debugging and isolation
  • Cross-platform development

Troubleshooting

"qemu-x86_64: command not found"

Install QEMU user mode (see Installation section above).

"qemu-system-x86_64 found but not qemu-x86_64"

You have QEMU system mode but need user mode. Install qemu-user package.

Program crashes or hangs

  • Check that your program has a main() function
  • Verify the program exits properly (the compiler now adds exit system calls automatically)
  • Try running natively first: ./output

System call errors

QEMU user mode translates system calls to the host system. Some advanced system calls may not be fully supported.