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The recompiler is configured via a TOML file that controls code generation behavior, analysis settings, and manual overrides.

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Required Fields

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project_name
string
default:"rex"
Project name used for generated files and namespaces.
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file_path
string
required
Path to the input XEX or ELF executable file to recompile.
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out_directory_path
string
default:"generated"
Output directory for generated C++ source files.

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Patch Files (Not Yet Implemented)

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patch_file_path
string
Path to binary patch file to apply before analysis.
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patch_file_path
string
Path to save the patched executable.

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Code Generation Options

These flags control register allocation and optimization behavior:
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skip_lr
boolean
default:false
Skip saving/restoring the Link Register (LR) when not modified. Reduces overhead for leaf functions.
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skip_msr
boolean
default:false
Skip Machine State Register (MSR) emulation. Use only if the binary doesn’t modify MSR.
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ctr_as_local
boolean
default:false
Allocate Count Register (CTR) as a local variable instead of state struct field. Improves performance when CTR is used locally.
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xer_as_local
boolean
default:false
Allocate XER (Fixed-Point Exception Register) as local variable.
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reserved_as_local
boolean
default:false
Allocate reserved registers (r2, r13) as local variables.
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cr_as_local
boolean
default:false
Allocate Condition Register fields as local variables.
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non_argument_as_local
boolean
default:false
Allocate non-argument registers (r11-r31) as local variables when not used for parameters.
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non_volatile_as_local
boolean
default:false
Allocate non-volatile registers (r14-r31) as local variables.
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generate_exception_handlers
boolean
default:false
Generate SEH (Structured Exception Handling) wrapper functions for Windows exception handling.

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Special Addresses

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longjmp_address
uint32
default:0
Address of longjmp function for setjmp/longjmp analysis. Use hex format: 0x82000100.
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setjmp_address
uint32
default:0
Address of setjmp function for setjmp/longjmp analysis.

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Analysis Section

Fine-tune the analysis pipeline: 
[analysis]
max_jump_extension = 65536
data_region_threshold = 16
large_function_threshold = 1048576
exception_handler_funcs = [0x82000200, 0x82000300]
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analysis.max_jump_extension
uint32
default:65536
Maximum bytes to extend function boundaries when jump table targets are found outside initial function size.
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analysis.data_region_threshold
uint32
default:16
Number of consecutive invalid instructions before marking region as data (not code). Helps detect embedded constants.
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analysis.large_function_threshold
uint32
default:1048576
Size in bytes (1MB default) to warn about unusually large functions. May indicate analysis errors.
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analysis.exception_handler_funcs
array
Array of exception handler function addresses for code region segmentation.
exception_handler_funcs = [0x82000200, 0x82000300]

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Invalid Instructions Hints

Mark regions that contain data (not code) to prevent disassembly errors: 
[[invalid_instructions]]
data = 0x82001000
size = 0x40

[[invalid_instructions]]
data = 0x82002000
size = 0x10
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invalid_instructions
array of tables
Array of data regions that should not be disassembled as code.Each entry requires:
  • data (uint32): Starting address of data region
  • size (uint32): Size of data region in bytes

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Indirect Call Hints

Mark bctr instructions as indirect calls (vtable dispatch, computed jumps) rather than switch tables: 
indirect_calls = [0x82000400, 0x82000800]
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indirect_calls
array
Array of addresses where bctr instructions are vtable/computed calls, not switch table jumps.

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Example Configuration

project_name = "mygame"
file_path = "default.xex"
out_directory_path = "generated"

# Enable optimizations
skip_lr = true
ctr_as_local = true
xer_as_local = true
cr_as_local = true

# Analysis settings
[analysis]
max_jump_extension = 131072  # 128KB
data_region_threshold = 20
large_function_threshold = 2097152  # 2MB

# Mark embedded constant table as data
[[invalid_instructions]]
data = 0x82100000
size = 0x1000

# Known indirect calls
indirect_calls = [0x82000450, 0x82000890]

# Manual function override
[functions."0x82000100"]
size = 0x400
name = "GameInit"

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Validation Rules

The configuration is validated before code generation:
  1. Alignment: All addresses must be 4-byte aligned (PowerPC instruction size)
  2. Required fields: file_path must be provided
  3. No overlaps: Function boundaries cannot overlap (standalone functions)
  4. Size constraints: Cannot specify both size and end for functions
  5. End address: If using end, it must be greater than the start address

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See Also

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