## lowhalf-notes.api
#
# Here we customize the generic 'note' facility with support for:
#
# Conditional-jump branch probabilities.
# Basic-block execution frequencies.
# Comments.
# No-reorder constraint on instructions in a basic block.
# Control-dependency definitions and uses.
# no_optimization flag.
# call-heapcleaner flag.
# heapcleaner-safepoint flag.
# heapcleaner_info flag.
# block-names.
# empty-block flag.
# mark-reg
# print-register-info.
# no branch-chaining.
# uses-virtual-frame-pointer flag.
# return_arg
# Compiled by:
# src/lib/compiler/back/low/lib/lowhalf.lib# Client packages can create their own annotations and propagate them;
# client-defined annotations are ignored by the backend lowhalf proper.
#
# TODO: There should be comments to say that the annotations are block
# or instruction annotations. -- Lal.
#
# See also:
#
# MLRISC Annotations
# Allen Leung, Lal George
# circa 1999, 14p
# http://www.smlnj.org//compiler-notes/annotations.ps
### "If the programmer can simulate a construct
### faster than a compiler can implement the
### construct itself, then the compiler writer
### has blown it badly."
### -- Guy Steele
stipulate
package nt = note; # note is from src/lib/src/note.pkg package rkj = registerkinds_junk; # registerkinds_junk is from src/lib/compiler/back/low/code/registerkinds-junk.pkgherein
api Lowhalf_Notes {
#
# The branch probability of conditional branches.
# The client can attach this with conditional branches.
# nnThis has no effect otherwise.
#
# Currently, the annotation is recognized by the static branch prediction
# mondule.
#
exception BRANCH_PROBABILITY probability::Probability;
branch_probability: nt::Notekind( probability::Probability );
# The execution frequency of a basic block
# You can attach this at a basic block.
#
exception EXECUTION_FREQUENCY Int;
execution_freq: nt::Notekind( Int );
# No effect at all; this just
# allows you to insert comments:
#
comment: nt::Notekind( String );
# Instructions in the block
# should not be reordered:
#
noreorder: nt::Notekind( Void );
# Control dependence definition and use.
#
# To use these, the client should generate
# control dependence virtual registers via cells::new_cell cells::CTRL
# and attach these annotations to instructions and basic blocks.
#
# These annotations are currently recognized by the SSA optimization
# modules.
#
exception CONTROL_DEPENDENCY_DEF rkj::Codetemp_Info;
exception CONTROL_DEPENDENCY_USE rkj::Codetemp_Info;
ctrl_def: nt::Notekind( rkj::Codetemp_Info );
ctrl_use: nt::Notekind( rkj::Codetemp_Info );
# Attach this annotation to assemblers
# for pretty printing client defined
# register information:
#
print_register_info: nt::Notekind (rkj::Codetemp_Info -> String);
heapcleaner_info: nt::Notekind( Void ); # Does the compilation unit have heapcleaner information?
no_optimization: nt::Notekind( Void ); # Disable all optimizations in the cccomponent.
# Mark basic block that calls the heapcleaner:
#
call_heapcleaner: nt::Notekind( Void );
heapcleaner_safepoint: nt::Notekind( String );
# Insert block names
#
exception BLOCKNAMES nt::Notes;
#
block_names: nt::Notekind( nt::Notes );
# This annotation inserts an empty basic block
#
exception EMPTYBLOCK;
empty_block: nt::Notekind( Void );
# Enter information for a register.
#
exception MARKREG rkj::Codetemp_Info -> Void;
mark_reg: nt::Notekind (rkj::Codetemp_Info -> Void);
no_branch_chaining: nt::Notekind( Void ); # Disable branch chaining optimization on a jump.
uses_virtual_framepointer: nt::Notekind( Void ); # Code has reference to the virtual frame pointer -- see src/lib/compiler/back/low/omit-framepointer/free-up-framepointer-in-machcode.api return_arg: nt::Notekind( rkj::Codetemp_Info ); # Define return arguments of a call (hack for intel32)
};
end;
## COPYRIGHT (c) 2002 Bell Labs, Lucent Technologies
## Subsequent changes by Jeff Prothero Copyright (c) 2010-2015,
## released per terms of SMLNJ-COPYRIGHT.