X-Git-Url: https://git.rrq.au/?a=blobdiff_plain;f=adoc%2Fp_branch.adoc;h=02f7319524a56e57218e68c6974fe9b51727c03c;hb=53f50810894e81457a75348b0565b4281d4762b4;hp=089e23867213f9164a4d23a9983e3b72ee9f1fd1;hpb=d5a8f559318ac57934871a48e964bac18557b601;p=rrq%2Frrqforth.git diff --git a/adoc/p_branch.adoc b/adoc/p_branch.adoc index 089e238..02f7319 100644 --- a/adoc/p_branch.adoc +++ b/adoc/p_branch.adoc @@ -11,3 +11,13 @@ Data stack: ( -- ) "BRANCH" is a function word that implements execution transfer by means of adding the subsequent branch offset to the point of execution. + +Note that the branch offset is a byte count and each FORTH word of a +definition take up a cell of 8 bytes. The offset is relative to the +cell address immediately subsequent to the offset cell. In other +words, offset 0 is not branching anywhere and an offset of -16 would +make a tight loop back to the branch instruction itself. The latter +would pull data stack values until and including the first zero value. + +See also <>, <>, <>, +<>, <> and <>.