Xenia-Canary/TODO.md

Instructions

stbu
lwzu

addx
addix
addic
addzex
subfx
subfex
subficx

mulli
mullwx
divwux

andix
orx

rlwinmx
rldiclx
extsbx
slwx
srawix

# can be no-op
dcbt
dcbtst

twi

Codegen

Tracing

Tracing modes:

• off (0)
• syscalls (1)
• fn calls (2)
• all instructions (3)

Inject extern functions into module:

• XeTraceKernelCall(caller_ia, cia, name, state)
• XeTraceUserCall(caller_ia, cia, name, state)
• XeTraceInstruction(cia, name, state)

Calling convention

Experiment with fastcc? May need typedef fn ptrs to call into the JITted code.

Indirect branches (ctr/lr)

emit_control.cc XeEmitBranchTo Need to take the value in LR/CTR and do something with it.

Return path:

• In SDB see if the function follows the 'return' semantic:
  • mfspr LR / mtspr LR/CTR / bcctr -- at end?
• In codegen add a BB that is just return.
• If a block 'returns', branch to the return BB.

Tail calls:

• If in a call BB check next BB.
• If next is a return, optimize to a tail call.

Fast path:

• Every time LR would be stashed, add the value of LR (some NIA) to a lookup table.
• When doing an indirect branch first lookup the address in the table.
• If not found, slow path, else jump.

Slow path:

• Call out and do an SDB lookup.
• If found, return, add to lookup table, and jump.
• If not found, need new function codegen!

Caching of register values in basic blocks

Right now the SSA values seem to leak from the blocks somehow. All caching is disabled.