diff options
Diffstat (limited to 'erts/emulator/internal_doc/beam_makeops.md')
| -rw-r--r-- | erts/emulator/internal_doc/beam_makeops.md | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/erts/emulator/internal_doc/beam_makeops.md b/erts/emulator/internal_doc/beam_makeops.md index 2880099b70..267af78412 100644 --- a/erts/emulator/internal_doc/beam_makeops.md +++ b/erts/emulator/internal_doc/beam_makeops.md @@ -1457,26 +1457,26 @@ all instructions. It expands to the address of the next instruction. Here is an example: i_call(CallDest) { - SET_CP(c_p, $NEXT_INSTRUCTION); + //| -no_next + $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION); $DISPATCH_REL($CallDest); } -When calling a function, the return address is first stored in `c_p->cp` -(using the `SET_CP()` macro defined in `beam_emu.c`), and then control is +When calling a function, the return address is first stored in `E[0]` +(using the `$SAVE_CONTINUATION_POINTER()` macro), and then control is transferred to the callee. Here is the generated code: OpCase(i_call_f): { - SET_CP(c_p, I+1); - ASSERT(VALID_INSTR(*(I + (fb(BeamExtraData(I[0]))) + 0))); - I += fb(BeamExtraData(I[0])) + 0;; - DTRACE_LOCAL_CALL(c_p, erts_code_to_codemfa(I)); - Dispatch();; + ASSERT(VALID_INSTR(*(I+2))); + *E = (BeamInstr) (I+2);; + + /* ... dispatch code intentionally left out ... */ } -We can see that that `$NEXT_INSTRUCTION` has been expanded to `I+1`. +We can see that that `$NEXT_INSTRUCTION` has been expanded to `I+2`. That makes sense since the size of the `i_call_f/1` instruction is -one word. +two words. ##### The IP_ADJUSTMENT pre-bound variable ##### |