[RFA:] Improve cgen/doc/rtl.texi wrt. timing and PROFILE.

[Hans-Peter Nilsson <hans-peter.nilsson@axis.com>]

Slight improvements to the documentation, I hope.

By the way, it seems toplevel configury does not create a
cgen/Makefile, necessary for "make info" to take effect, even
though nothing else is created object-wise.  Needs fixing.

Ok to commit?

	* doc/rtl.texi (Model variants): Mention current limitations for
	unit inputs and outputs.
	(Hardware elements) <attribute PROFILE>: Be slightly more
	verbose.
	(Instructions) <timing>: input/output overrides have a direction
	operand.

Index: rtl.texi
===================================================================
RCS file: /cvs/src/src/cgen/doc/rtl.texi,v
retrieving revision 1.15
diff -c -p -r1.15 rtl.texi
*** rtl.texi	29 Jan 2002 22:51:52 -0000	1.15
--- rtl.texi	30 Nov 2002 08:13:20 -0000
*************** function unit called @samp{u-cmp} is def
*** 755,761 ****
  This handles instructions that use src1 and src2 as operands.  The
  organization of units is arbitrary.  On the M32R, src1/src2 instructions
  are typically compare instructions so a separate function unit was
! created for them.
  
  @node Hardware elements
  @section Hardware Elements
--- 755,763 ----
  This handles instructions that use src1 and src2 as operands.  The
  organization of units is arbitrary.  On the M32R, src1/src2 instructions
  are typically compare instructions so a separate function unit was
! created for them.  Current limitations require that each hardware item
! behind the operands must be marked with the attribute @code{PROFILE} and
! the hardware item must not be scalar.
  
  @node Hardware elements
  @section Hardware Elements
*************** with @code{VIRTUAL} (??? revisit).
*** 813,820 ****
  
  @item PROFILE
  
! Ignore.  This is a work-in-progress to define how to profile references
! to hardware elements.
  
  @item VIRTUAL
  
--- 815,823 ----
  
  @item PROFILE
  
! This attribute must be present for hardware elements to which references
! are profiled.  Beware, this is work-in-progress.  If you use this
! attribute it is likely you have to hack CGEN.  (Please submit patches.)
  
  @item VIRTUAL
  
*************** that supports the instruction.  The defa
*** 1866,1879 ****
  The syntax is:
  
  @example
! (mach-name (unit name (unit-var-name1 insn-operand-name1)
!                       (unit-var-name2 insn-operand-name2)
                        ...
                        (cycles cycle-count))
  @end example
  
! unit-var-name/insn-operand-name mappings are optional.
! They map unit inputs/outputs to semantic elements.
  
  @code{cycles} overrides the @code{done} value (latency) of the function
  unit and is optional.
--- 1869,1885 ----
  The syntax is:
  
  @example
! (mach-name (unit name (direction unit-var-name1 insn-operand-name1)
!                       (direction unit-var-name2 insn-operand-name2)
                        ...
                        (cycles cycle-count))
  @end example
  
! direction/unit-var-name/insn-operand-name mappings are optional.
! They map unit inputs/outputs to semantic elements.  The
! direction specifier can be @code{in} or @code{out} mapping the
! name of a unit input or output, respectively, to an insn
! operand.
  
  @code{cycles} overrides the @code{done} value (latency) of the function
  unit and is optional.

brgds, H-P