From a32ed5df6aa31aa5a38a55af9d75880e906721f2 Mon Sep 17 00:00:00 2001 From: xleroy Date: Sat, 10 Apr 2010 12:15:43 +0000 Subject: Coloring: allow to exclude user-specified registers from allocation. CPragmas (PPC/EABI only): add #pragma reserve_register git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@1314 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e --- backend/Coloringaux.ml | 65 +++++++++++++++++++++++++++++------------------- backend/Coloringaux.mli | 2 ++ powerpc/Machregsaux.ml | 45 +++++++++++++++++++++++++++++++++ powerpc/Machregsaux.mli | 16 ++++++++++++ powerpc/eabi/CPragmas.ml | 31 ++++++++++++++++++++--- 5 files changed, 131 insertions(+), 28 deletions(-) create mode 100644 powerpc/Machregsaux.ml create mode 100644 powerpc/Machregsaux.mli diff --git a/backend/Coloringaux.ml b/backend/Coloringaux.ml index 9b657697..04cc1ee2 100644 --- a/backend/Coloringaux.ml +++ b/backend/Coloringaux.ml @@ -167,6 +167,42 @@ module IntPairSet = Set.Make(struct 0 end) +(* Register classes *) + +let class_of_type = function Tint -> 0 | Tfloat -> 1 + +let num_register_classes = 2 + +let caller_save_registers = Array.make num_register_classes [||] + +let callee_save_registers = Array.make num_register_classes [||] + +let num_available_registers = Array.make num_register_classes 0 + +let reserved_registers = ref ([]: mreg list) + +let rec remove_reserved = function + | [] -> [] + | hd :: tl -> + if List.mem hd !reserved_registers + then remove_reserved tl + else hd :: remove_reserved tl + +let init_regs() = + caller_save_registers.(0) <- + Array.of_list (remove_reserved Conventions.int_caller_save_regs); + caller_save_registers.(1) <- + Array.of_list (remove_reserved Conventions.float_caller_save_regs); + callee_save_registers.(0) <- + Array.of_list (remove_reserved Conventions.int_callee_save_regs); + callee_save_registers.(1) <- + Array.of_list (remove_reserved Conventions.float_callee_save_regs); + for i = 0 to num_register_classes - 1 do + num_available_registers.(i) <- + Array.length caller_save_registers.(i) + + Array.length callee_save_registers.(i) + done + (* \subsection{The George-Appel algorithm} *) (* Below is a straigthforward translation of the pseudo-code at the end @@ -208,7 +244,7 @@ let nextRegIdent = ref 0 (* Initialization of all global data structures *) -let init() = +let init_graph() = adjSet := IntPairSet.empty; nextRegIdent := 0; DLinkNode.clear simplifyWorklist; @@ -268,28 +304,6 @@ let nodeMoves n = let moveRelated n = List.exists moveIsActiveOrWorklist n.movelist -(* Register classes *) - -let class_of_type = function Tint -> 0 | Tfloat -> 1 - -let num_register_classes = 2 - -let caller_save_registers = [| - Array.of_list Conventions.int_caller_save_regs; - Array.of_list Conventions.float_caller_save_regs -|] - -let callee_save_registers = [| - Array.of_list Conventions.int_callee_save_regs; - Array.of_list Conventions.float_callee_save_regs -|] - -let num_available_registers = - [| Array.length caller_save_registers.(0) - + Array.length callee_save_registers.(0); - Array.length caller_save_registers.(1) - + Array.length callee_save_registers.(1) |] - (*i (* Check invariants *) @@ -689,11 +703,12 @@ let spill_costs f = Hashtbl.create 7 let graph_coloring (f: coq_function) (g: graph) (env: regenv) (regs: Regset.t) : (reg -> loc) = - init(); + init_regs(); + init_graph(); Array.fill start_points 0 num_register_classes 0; let mapping = build g env (spill_costs f) in List.iter assign_color (nodeOrder []); - init(); + init_graph(); (* free data structures *) fun r -> try location_of_node (getAlias (Hashtbl.find mapping r)) with Not_found -> R IT1 (* any location *) diff --git a/backend/Coloringaux.mli b/backend/Coloringaux.mli index c5070f20..7597c7ca 100644 --- a/backend/Coloringaux.mli +++ b/backend/Coloringaux.mli @@ -18,3 +18,5 @@ open InterfGraph val graph_coloring: coq_function -> graph -> regenv -> Regset.t -> (reg -> loc) + +val reserved_registers: Machregs.mreg list ref diff --git a/powerpc/Machregsaux.ml b/powerpc/Machregsaux.ml new file mode 100644 index 00000000..b729d100 --- /dev/null +++ b/powerpc/Machregsaux.ml @@ -0,0 +1,45 @@ +(* *********************************************************************) +(* *) +(* The Compcert verified compiler *) +(* *) +(* Xavier Leroy, INRIA Paris-Rocquencourt *) +(* *) +(* Copyright Institut National de Recherche en Informatique et en *) +(* Automatique. All rights reserved. This file is distributed *) +(* under the terms of the INRIA Non-Commercial License Agreement. *) +(* *) +(* *********************************************************************) + +(** Auxiliary functions on machine registers *) + +open Machregs + +let register_names = [ + ("R3", R3); ("R4", R4); ("R5", R5); ("R6", R6); + ("R7", R7); ("R8", R8); ("R9", R9); ("R10", R10); + ("R14", R14); ("R15", R15); ("R16", R16); + ("R17", R17); ("R18", R18); ("R19", R19); ("R20", R20); + ("R21", R21); ("R22", R22); ("R23", R23); ("R24", R24); + ("R25", R25); ("R26", R26); ("R27", R27); ("R28", R28); + ("R29", R29); ("R30", R30); ("R31", R31); + ("F1", F1); ("F2", F2); ("F3", F3); ("F4", F4); + ("F5", F5); ("F6", F6); ("F7", F7); ("F8", F8); + ("F9", F9); ("F10", F10); ("F14", F14); ("F15", F15); + ("F16", F16); ("F17", F17); ("F18", F18); ("F19", F19); + ("F20", F20); ("F21", F21); ("F22", F22); ("F23", F23); + ("F24", F24); ("F25", F25); ("F26", F26); ("F27", F27); + ("F28", F28); ("F29", F29); ("F30", F30); ("F31", F31); + ("R11", IT1); ("R0", IT2); + ("F11", FT1); ("F12", FT2); ("F0", FT3) +] + +let register_by_name s = + try + Some(List.assoc (String.uppercase s) register_names) + with Not_found -> + None + +let can_reserve_register r = + List.mem r Conventions.int_callee_save_regs + || List.mem r Conventions.float_callee_save_regs + diff --git a/powerpc/Machregsaux.mli b/powerpc/Machregsaux.mli new file mode 100644 index 00000000..6d819882 --- /dev/null +++ b/powerpc/Machregsaux.mli @@ -0,0 +1,16 @@ +(* *********************************************************************) +(* *) +(* The Compcert verified compiler *) +(* *) +(* Xavier Leroy, INRIA Paris-Rocquencourt *) +(* *) +(* Copyright Institut National de Recherche en Informatique et en *) +(* Automatique. All rights reserved. This file is distributed *) +(* under the terms of the INRIA Non-Commercial License Agreement. *) +(* *) +(* *********************************************************************) + +(** Auxiliary functions on machine registers *) + +val register_by_name: string -> Machregs.mreg option +val can_reserve_register: Machregs.mreg -> bool diff --git a/powerpc/eabi/CPragmas.ml b/powerpc/eabi/CPragmas.ml index 4bb7786e..3104cc88 100644 --- a/powerpc/eabi/CPragmas.ml +++ b/powerpc/eabi/CPragmas.ml @@ -68,6 +68,8 @@ let _ = sec_near_access = false} ] +(* #pragma section *) + let process_section_pragma classname istring ustring addrmode accmode = let old_si = try Hashtbl.find section_table classname @@ -85,6 +87,7 @@ let process_section_pragma classname istring ustring addrmode accmode = else (addrmode = "near-code") || (addrmode = "near-data") } in Hashtbl.add section_table classname si +(* #pragma use_section *) let use_section_table : (AST.ident, section_info) Hashtbl.t = Hashtbl.create 51 @@ -122,6 +125,19 @@ let define_variable id d = if is_small !Clflags.option_small_data then "SDATA" else "DATA" in default_use_section id sect +(* #pragma reserve_register *) + +let process_reserve_register_pragma name = + match Machregsaux.register_by_name name with + | None -> + C2Clight.error "unknown register in `reserve_register' pragma" + | Some r -> + if Machregsaux.can_reserve_register r then + Coloringaux.reserved_registers := + r :: !Coloringaux.reserved_registers + else + C2Clight.error "cannot reserve this register (not a callee-save)" + (* Parsing of pragmas using regexps *) let re_start_pragma_section = Str.regexp "section\\b" @@ -144,6 +160,11 @@ let re_pragma_use_section = Str.regexp let re_split_idents = Str.regexp "[ \t,]+" +let re_start_pragma_reserve_register = Str.regexp "reserve_register\\b" + +let re_pragma_reserve_register = Str.regexp + "reserve_register[ \t]+\\([A-Za-z0-9]+\\)" + let process_pragma name = if Str.string_match re_pragma_section name 0 then begin process_section_pragma @@ -162,9 +183,13 @@ let process_pragma name = if identlist = [] then C2Clight.warning "vacuous `use_section' pragma"; List.iter (process_use_section_pragma classname) identlist; true - end else if Str.string_match re_start_pragma_use_section name 0 then - (C2Clight.error "ill-formed `use_section' pragma"; true) - else + end else if Str.string_match re_start_pragma_use_section name 0 then begin + C2Clight.error "ill-formed `use_section' pragma"; true + end else if Str.string_match re_pragma_reserve_register name 0 then begin + process_reserve_register_pragma (Str.matched_group 1 name); true + end else if Str.string_match re_start_pragma_reserve_register name 0 then begin + C2Clight.error "ill-formed `reserve_register' pragma"; true + end else false let initialize () = -- cgit