Bharati Bhole writes:
> On 11/2/06, Andrew Haley <aph@redhat.com> wrote:
> > Bharati Bhole writes:
> > > On 11/2/06, Daniel Berlin <dberlin@dberlin.org> wrote:
> > > > > I want to know what part of rtx each field in this structure stores.
> > > > > While tracing through gdb i tried to print the rtx, and i was not able
> > > > > to understand that. Could u please explain me it with a sample RTX
> > > > > that what value these fields have.
> > > > >
> > > >
> > > > The macros used to access the rtl fields in rtl.h explain what part of
> > > > each field they access and what they treat that object as.
> > > >
> > > > The definitions of rtl in rtl.def define what each portion of a piece
> > > > of valid RTL is structured as.
> > > > > Bharati.
> > > > >
> > > >
> > >
> > > I have gone through the structure but i still dont get it.
> > > Could anybody please tell me, if the following insn is a sample insn,
> > > how will the rtx structure look like -
> > > (define_insn "subsi3_carry_zext"
> > > [(set (match_operand:DI 0 "register_operand" "=rm,r")
> > > (zero_extend:DI
> > > (minus:SI (match_operand:SI 1 "register_operand" "0,0")
> > > (plus:SI (match_operand:SI 3
> > > "ix86_carry_flag_operator" "")
> > > (match_operand:SI 2 "general_operand" "ri,rm")))))
> > > (clobber (reg:CC FLAGS_REG))]
> > > "TARGET_64BIT && ix86_binary_operator_ok (MINUS, SImode, operands)"
> > > "sbb{l}\t{%2, %k0|%k0, %2}"
> > > [(set_attr "type" "alu")
> > > (set_attr "pent_pair" "pu")
> > > (set_attr "mode" "SI")])
> >
> > But this isn't a simple insn, it's a machine description pattern.
> > These are described in Section 13, Machine Descriptions.
> Yes, this is a machine description pattern. In the genrecog.c file the
> .md file is read and from each insn the RTL template is filled in the
> RTX structure. So i want to know that how this insn ie the RTL teplate
> from this insn will be filled in the RTX structure. I mean what part
> of the template, each field of RTX structure will store? Could anybody
> please tell me that?
Possibly, but it would be better for you to find out for yourself.
Have you tried putting a breakpoint on make_insn_raw ?
Andrew.