@samp{arg1} becomes the most significant part of the result.
Each argument is interpreted in mode @samp{in-mode}.
@samp{in-mode} must evenly divide @samp{out-mode}.
-@c ??? Endianness issues have yet to be decided.
-@c Blech. Time to decide them.
@item (sequence mode ((mode1 local1) ...) expr1 ...)
Execute @samp{expr1}, @samp{expr2}, etc. sequentially.
; Combine smaller modes into a larger one.
; Arguments are specified most significant to least significant.
-; ??? May also want an endian dependent argument order. That can be
-; implemented on top of or beside this.
; ??? Not all of the combinations are supported in the simulator.
; They'll get added as necessary.
(drn (join &options &out-mode in-mode arg1 . arg-rest)
; GCC's subreg.
; Called subword 'cus it's not exactly subreg.
-; Word numbering is from most significant (word 0) to least (word N-1).
-; ??? May also want an endian dependent word ordering. That can be
-; implemented on top of or beside this.
+; Word numbering is word-order dependent.
+; Word number 0 is the most significant word if big-endian-words.
+; Word number 0 is the least significant word if little-endian-words.
; ??? GCC plans to switch to SUBREG_BYTE. Keep an eye out for the switch
; (which is extensive so probably won't happen anytime soon).
+; MODE is the mode of the result, not operand0.
;
; The mode spec of operand0 use to be MATCHEXPR, but subword is not a normal rtx.
; The mode of operand0 is not necessarily the same as the mode of the result,
; (c-call mode name arg1 arg2 ...)
; which is converted into a C function call:
; name (current_cpu, arg1, arg2, ...)
-; Mode is the mode of the result.
+; MODE is the mode of the result.
; If it is VOID this call is a statement and ';' is appended.
; Otherwise it is part of an expression.
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