689 lines
22 KiB
Plaintext
689 lines
22 KiB
Plaintext
(***********************************************************************)
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(* *)
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(* Caml Special Light *)
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(* *)
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(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
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(* *)
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(* Copyright 1995 Institut National de Recherche en Informatique et *)
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(* Automatique. Distributed only by permission. *)
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(* *)
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(***********************************************************************)
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(* $Id$ *)
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(* Emission of Intel 386 assembly code *)
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open Misc
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open Cmm
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open Arch
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open Proc
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open Reg
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open Mach
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open Linearize
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open Emitaux
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(* Tradeoff between code size and code speed *)
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let fastcode_flag = ref true
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let stack_offset = ref 0
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(* Layout of the stack frame *)
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let frame_size () = (* includes return address *)
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!stack_offset + 4 * num_stack_slots.(0) + 8 * num_stack_slots.(1) + 4
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let slot_offset loc class =
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match loc with
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Incoming n -> frame_size() + n
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| Local n ->
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if class = 0
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then !stack_offset + n * 4
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else !stack_offset + num_stack_slots.(0) * 4 + n * 8
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| Outgoing n -> n
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(* Symbols are prefixed with _, except under Linux with ELF binaries *)
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let symbol_prefix =
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match Config.system with
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"linux_elf" -> ""
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| _ -> "_"
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let emit_symbol s =
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emit_string symbol_prefix; Emitaux.emit_symbol s
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(* Output a label *)
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let label_prefix =
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match Config.system with
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"linux_elf" -> ".L"
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| _ -> "L"
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let emit_label lbl =
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emit_string label_prefix; emit_int lbl
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(* Output a .align directive.
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The numerical argument to .align is log2 of alignment size, except
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under ELF, where it is the alignment size... *)
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let emit_align =
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match Config.system with
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"linux_elf" -> (fun n -> ` .align {emit_int n}\n`)
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| _ -> (fun n -> ` .align {emit_int(Misc.log2 n)}\n`)
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(* Output a pseudo-register *)
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let emit_reg r =
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match r.loc with
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Reg r ->
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emit_string (register_name r)
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| Stack s ->
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let ofs = slot_offset s (register_class r) in
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`{emit_int ofs}(%esp)`
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| Unknown ->
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fatal_error "Emit_i386.emit_reg"
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(* Same, but after one push in the floating-point register set *)
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let emit_shift r =
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match r.loc with
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Reg r ->
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emit_string (register_name(r + 1))
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| Stack s ->
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let ofs = slot_offset s (register_class r) in
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`{emit_int ofs}(%esp)`
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| Unknown ->
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fatal_error "Emit_i386.emit_shift"
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(* Output a reference to the lower 8 bits or lower 16 bits of a register *)
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let reg_low_byte_name = [| "%al"; "%bl"; "%cl"; "%dl" |]
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let reg_low_half_name = [| "%ax"; "%bx"; "%cx"; "%dx"; "%si"; "%di"; "%bp" |]
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let emit_reg8 r =
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match r.loc with
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Reg r when r < 4 -> emit_string (reg_low_byte_name.(r))
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| _ -> fatal_error "Emit_i386.emit_reg8"
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let emit_reg16 r =
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match r.loc with
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Reg r when r < 7 -> emit_string (reg_low_half_name.(r))
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| _ -> fatal_error "Emit_i386.emit_reg16"
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(* Check if the given register overlaps (same location) with the given
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array of registers *)
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let register_overlap reg arr =
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try
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for i = 0 to Array.length arr - 1 do
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if reg.loc = arr.(i).loc then raise Exit
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done;
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false
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with Exit ->
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true
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(* Check if a set of registers contains a float *)
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let contains_floats arr =
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try
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for i = 0 to Array.length arr - 1 do
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if arr.(i).typ = Float then raise Exit
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done;
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false
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with Exit ->
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true
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(* Output an addressing mode *)
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let emit_addressing addr r n =
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match addr with
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Ibased(s, d) ->
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`{emit_symbol s}`;
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if d <> 0 then ` + {emit_int d}`
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| Iindexed d ->
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if d <> 0 then emit_int d;
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`({emit_reg r.(n)})`
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| Iindexed2 d ->
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if d <> 0 then emit_int d;
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`({emit_reg r.(n)}, {emit_reg r.(n+1)})`
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| Iscaled(scale, d) ->
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if d <> 0 then emit_int d;
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`(, {emit_reg r.(n)}, {emit_int scale})`
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| Iindexed2scaled(scale, d) ->
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if d <> 0 then emit_int d;
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`({emit_reg r.(n)}, {emit_reg r.(n+1)}, {emit_int scale})`
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(* Record live pointers at call points *)
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type frame_descr =
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{ fd_lbl: int; (* Return address *)
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fd_frame_size: int; (* Size of stack frame *)
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fd_live_offset: int list } (* Offsets/regs of live addresses *)
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let frame_descriptors = ref([] : frame_descr list)
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let record_frame_label live =
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let lbl = new_label() in
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let live_offset = ref [] in
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Reg.Set.iter
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(function
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{typ = Addr; loc = Reg r} ->
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live_offset := (-1 - r) :: !live_offset
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| {typ = Addr; loc = Stack s} as reg ->
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live_offset := slot_offset s (register_class reg) :: !live_offset
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| _ -> ())
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live;
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frame_descriptors :=
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{ fd_lbl = lbl;
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fd_frame_size = frame_size();
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fd_live_offset = !live_offset } :: !frame_descriptors;
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lbl
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let record_frame live =
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let lbl = record_frame_label live in `{emit_label lbl}:`
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let emit_frame fd =
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` .long {emit_label fd.fd_lbl}\n`;
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` .word {emit_int fd.fd_frame_size}\n`;
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` .word {emit_int (List.length fd.fd_live_offset)}\n`;
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List.iter
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(fun n ->
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` .word {emit_int n}\n`)
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fd.fd_live_offset;
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emit_align 4
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(* Names for instructions *)
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let instr_for_intop = function
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Iadd -> "addl"
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| Isub -> "subl"
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| Imul -> "imull"
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| Iand -> "andl"
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| Ior -> "orl"
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| Ixor -> "xorl"
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| Ilsl -> "sal"
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| Ilsr -> "shr"
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| Iasr -> "sar"
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| _ -> fatal_error "Emit_i386: instr_for_intop"
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let name_for_cond_branch = function
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Isigned Ceq -> "e" | Isigned Cne -> "ne"
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| Isigned Cle -> "le" | Isigned Cgt -> "g"
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| Isigned Clt -> "l" | Isigned Cge -> "ge"
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| Iunsigned Ceq -> "e" | Iunsigned Cne -> "ne"
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| Iunsigned Cle -> "be" | Iunsigned Cgt -> "a"
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| Iunsigned Clt -> "b" | Iunsigned Cge -> "ae"
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(* Output an = 0 or <> 0 test. *)
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let output_test_zero arg =
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match arg.loc with
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Reg r -> ` testl {emit_reg arg}, {emit_reg arg}\n`
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| _ -> ` cmpl $0, {emit_reg arg}\n`
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(* Deallocate the stack frame before a return or tail call *)
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let output_epilogue () =
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match frame_size() - 4 with
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0 -> ()
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| 4 -> ` popl %esi\n` (* Faster than add, and %esi is dead here *)
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| n -> ` addl ${emit_int n}, %esp\n`
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(* Output the assembly code for an instruction *)
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(* Name of current function *)
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let function_name = ref ""
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(* Entry point for tail recursive calls *)
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let tailrec_entry_point = ref 0
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(* Label of trap for out-of-range accesses *)
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let range_check_trap = ref 0
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let float_constants = ref ([] : (int * string) list)
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let emit_instr i =
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match i.desc with
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Lend -> ()
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| Lop(Imove | Ispill | Ireload) ->
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if i.arg.(0).loc <> i.res.(0).loc then begin
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match i.arg.(0).typ with
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Int | Addr ->
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` movl {emit_reg i.arg.(0)}, {emit_reg i.res.(0)}\n`
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| Float ->
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if i.arg.(0).loc = Reg 100 then
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` fstl {emit_reg i.res.(0)}\n`
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else begin
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` fldl {emit_reg i.arg.(0)}\n`;
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` fstpl {emit_shift i.res.(0)}\n`
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end
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end
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| Lop(Iconst_int 0) ->
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begin match i.res.(0).loc with
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Reg n -> ` xorl {emit_reg i.res.(0)}, {emit_reg i.res.(0)}\n`
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| _ -> ` movl $0, {emit_reg i.res.(0)}\n`
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end
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| Lop(Iconst_int n) ->
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` movl ${emit_int n}, {emit_reg i.res.(0)}\n`
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| Lop(Iconst_float f) ->
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if float_of_string f = 0.0 then
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` fldz\n`
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else begin
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let lbl = new_label() in
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float_constants := (lbl, f) :: !float_constants;
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` fldl {emit_label lbl}\n`
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end;
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` fstpl {emit_shift i.res.(0)}\n`
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| Lop(Iconst_symbol s) ->
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` movl ${emit_symbol s}, {emit_reg i.res.(0)}\n`
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| Lop(Icall_ind) ->
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` call *{emit_reg i.arg.(0)}\n`;
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record_frame i.live
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| Lop(Icall_imm s) ->
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` call {emit_symbol s}\n`;
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record_frame i.live
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| Lop(Itailcall_ind) ->
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output_epilogue();
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` jmp *{emit_reg i.arg.(0)}\n`
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| Lop(Itailcall_imm s) ->
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if s = !function_name then
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` jmp {emit_label !tailrec_entry_point}\n`
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else begin
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output_epilogue();
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` jmp {emit_symbol s}\n`
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end
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| Lop(Iextcall(s, alloc)) ->
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if alloc then begin
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` movl ${emit_symbol s}, %eax\n`;
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` call {emit_symbol "caml_c_call"}\n`;
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record_frame i.live
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end else if contains_floats i.arg or contains_floats i.res then begin
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` movl ${emit_symbol s}, %eax\n`;
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` call {emit_symbol "caml_c_call_noalloc"}\n`
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end else
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` call {emit_symbol s}\n`;
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if Array.length i.res > 0 & i.res.(0).typ = Float then
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` fstpl {emit_shift i.res.(0)}\n`
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| Lop(Istackoffset n) ->
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if n >= 0
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then ` subl ${emit_int n}, %esp\n`
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else ` addl ${emit_int(-n)}, %esp\n`;
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stack_offset := !stack_offset + n
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| Lop(Iload(chunk, addr)) ->
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let dest = i.res.(0) in
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begin match dest.typ with
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Int | Addr ->
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begin match (chunk, dest.loc) with
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(Word, _) ->
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` movl {emit_addressing addr i.arg 0}, {emit_reg dest}\n`
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| (Byte_unsigned, Reg r) when r < 4 & not (register_overlap dest i.arg) ->
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` xorl {emit_reg dest}, {emit_reg dest}\n`;
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` movb {emit_addressing addr i.arg 0}, {emit_reg8 dest}\n`
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| (Byte_unsigned, _) ->
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` movzbl {emit_addressing addr i.arg 0}, {emit_reg dest}\n`
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| (Byte_signed, _) ->
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` movsbl {emit_addressing addr i.arg 0}, {emit_reg dest}\n`
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| (Sixteen_unsigned, Reg r) when not (register_overlap dest i.arg) ->
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` xorl {emit_reg dest}, {emit_reg dest}\n`;
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` movw {emit_addressing addr i.arg 0}, {emit_reg16 dest}\n`
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| (Sixteen_unsigned, _) ->
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` movzwl {emit_addressing addr i.arg 0}, {emit_reg dest}\n`
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| (Sixteen_signed, _) ->
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` movswl {emit_addressing addr i.arg 0}, {emit_reg dest}\n`
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end
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| Float ->
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` fldl {emit_addressing addr i.arg 0}\n`;
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` fstpl {emit_shift i.res.(0)}\n`
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end
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| Lop(Istore(Word, addr)) ->
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begin match i.arg.(0).typ with
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Int | Addr ->
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` movl {emit_reg i.arg.(0)}, {emit_addressing addr i.arg 1}\n`
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| Float ->
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if i.arg.(0).loc = Reg 100 then
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` fstl {emit_addressing addr i.arg 1}\n`
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else begin
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` fldl {emit_reg i.arg.(0)}\n`;
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` fstpl {emit_addressing addr i.arg 1}\n`
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end
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end
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| Lop(Istore(chunk, addr)) ->
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(* i.arg.(0) is guaranteed to be in %edx, actually *)
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begin match chunk with
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Word -> fatal_error "Emit_i386: store word"
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| Byte_unsigned | Byte_signed ->
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` movb {emit_reg8 i.arg.(0)}, {emit_addressing addr i.arg 1}\n`
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| Sixteen_unsigned | Sixteen_signed ->
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` movw {emit_reg16 i.arg.(0)}, {emit_addressing addr i.arg 1}\n`
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end
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| Lop(Ialloc n) ->
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if !fastcode_flag then begin
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` movl {emit_symbol "young_ptr"}, %eax\n`;
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` subl ${emit_int n}, %eax\n`;
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` movl %eax, {emit_symbol "young_ptr"}\n`;
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` cmpl {emit_symbol "young_start"}, %eax\n`;
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let lbl_cont = record_frame_label i.live in
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` jae {emit_label lbl_cont}\n`;
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` call {emit_symbol "caml_call_gc"}\n`;
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` .word {emit_int n}\n`;
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`{emit_label lbl_cont}: leal 4(%eax), {emit_reg i.res.(0)}\n`
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end else begin
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begin match n with
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8 -> ` call {emit_symbol "caml_alloc1"}\n`
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| 12 -> ` call {emit_symbol "caml_alloc2"}\n`
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| 16 -> ` call {emit_symbol "caml_alloc3"}\n`
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| _ -> ` movl ${emit_int n}, %eax\n`;
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` call {emit_symbol "caml_alloc"}\n`
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end;
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`{record_frame i.live} leal 4(%eax), {emit_reg i.res.(0)}\n`
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end
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| Lop(Iintop(Icomp cmp)) ->
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` cmpl {emit_reg i.arg.(1)}, {emit_reg i.arg.(0)}\n`;
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let b = name_for_cond_branch cmp in
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` set{emit_string b} %al\n`;
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` movzbl %al, {emit_reg i.res.(0)}\n`
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| Lop(Iintop_imm(Icomp cmp, n)) ->
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` cmpl ${emit_int n}, {emit_reg i.arg.(0)}\n`;
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let b = name_for_cond_branch cmp in
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` set{emit_string b} %al\n`;
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` movzbl %al, {emit_reg i.res.(0)}\n`
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| Lop(Iintop Icheckbound) ->
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if !range_check_trap = 0 then range_check_trap := new_label();
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` cmpl {emit_reg i.arg.(1)}, {emit_reg i.arg.(0)}\n`;
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` jbe {emit_label !range_check_trap}\n`
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| Lop(Iintop_imm(Icheckbound, n)) ->
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if !range_check_trap = 0 then range_check_trap := new_label();
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` cmpl ${emit_int n}, {emit_reg i.arg.(0)}\n`;
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` jbe {emit_label !range_check_trap}\n`
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| Lop(Iintop(Idiv | Imod)) ->
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` cltd\n`;
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` idivl {emit_reg i.arg.(1)}\n`
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| Lop(Iintop(Ilsl | Ilsr | Iasr as op)) ->
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(* We have i.arg.(0) = i.res.(0) and i.arg.(1) = %ecx *)
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` {emit_string(instr_for_intop op)} %cl, {emit_reg i.res.(0)}\n`
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| Lop(Iintop op) ->
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(* We have i.arg.(0) = i.res.(0) *)
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` {emit_string(instr_for_intop op)} {emit_reg i.arg.(1)}, {emit_reg i.res.(0)}\n`
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| Lop(Iintop_imm(Iadd, 1) | Iintop_imm(Isub, -1)) ->
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` incl {emit_reg i.res.(0)}\n`
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| Lop(Iintop_imm(Iadd, -1) | Iintop_imm(Isub, 1)) ->
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` decl {emit_reg i.res.(0)}\n`
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| Lop(Iintop_imm(op, n)) ->
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(* We have i.arg.(0) = i.res.(0) *)
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` {emit_string(instr_for_intop op)} ${emit_int n}, {emit_reg i.res.(0)}\n`
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| Lop(Iaddf | Isubf | Imulf | Idivf as floatop) ->
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fatal_error "Emit_i386: floatop"
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| Lop(Ifloatofint) ->
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begin match i.arg.(0).loc with
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Stack s ->
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` fildl {emit_reg i.arg.(0)}\n`;
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` fstpl {emit_shift i.res.(0)}\n`
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| _ ->
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` pushl {emit_reg i.arg.(0)}\n`;
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stack_offset := !stack_offset + 4;
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` fildl (%esp)\n`;
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` fstpl {emit_shift i.res.(0)}\n`;
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` addl $4, %esp\n`;
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stack_offset := !stack_offset - 4
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end
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| Lop(Iintoffloat) ->
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stack_offset := !stack_offset - 8;
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` subl $8, %esp\n`;
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` fnstcw 4(%esp)\n`;
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` movl 4(%esp), %eax\n`;
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` movb $12, %ah\n`;
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` movl %eax, (%esp)\n`;
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` fldcw (%esp)\n`;
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` fldl {emit_reg i.arg.(0)}\n`;
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begin match i.res.(0).loc with
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Stack s ->
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` fistpl {emit_shift i.res.(0)}\n`
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| _ ->
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` fistpl (%esp)\n`;
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` movl (%esp), {emit_reg i.res.(0)}\n`
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end;
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` fldcw 4(%esp)\n`;
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` addl $8, %esp\n`;
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stack_offset := !stack_offset + 8
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| Lop(Ispecific(Ilea addr)) ->
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` lea {emit_addressing addr i.arg 0}, {emit_reg i.res.(0)}\n`
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| Lop(Ispecific(Istore_int(n, addr))) ->
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` movl ${emit_int n}, {emit_addressing addr i.arg 0}\n`
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| Lop(Ispecific(Istore_symbol(s, addr))) ->
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` movl ${emit_symbol s}, {emit_addressing addr i.arg 0}\n`
|
|
| Lop(Ispecific(Ioffset_loc(n, addr))) ->
|
|
` addl ${emit_int n}, {emit_addressing addr i.arg 0}\n`
|
|
| Lop(Ispecific(Ifloatarith(op, addr_arg1, addr_arg2, addr_res))) ->
|
|
let pos_arg2 =
|
|
match addr_arg1 with
|
|
None -> 1 | Some addr -> num_args_addressing addr in
|
|
let pos_res =
|
|
pos_arg2 +
|
|
(match addr_arg2 with
|
|
None -> 1 | Some addr -> num_args_addressing addr) in
|
|
let instr =
|
|
match op with
|
|
Ifloatadd -> "fadd"
|
|
| Ifloatsub -> "fsub"
|
|
| Ifloatmul -> "fmul"
|
|
| Ifloatdiv -> "fdiv" in
|
|
begin match addr_arg1 with
|
|
Some addr ->
|
|
` fldl {emit_addressing addr i.arg 0}\n`
|
|
| None ->
|
|
` fldl {emit_reg i.arg.(0)}\n`
|
|
end;
|
|
begin match addr_arg2 with
|
|
Some addr ->
|
|
` {emit_string instr}l {emit_addressing addr i.arg pos_arg2}\n`
|
|
| None ->
|
|
match i.arg.(1).loc with
|
|
Stack s ->
|
|
` {emit_string instr}l {emit_shift i.arg.(pos_arg2)}\n`
|
|
| _ ->
|
|
` {emit_string instr} {emit_shift i.arg.(pos_arg2)}\n`
|
|
end;
|
|
begin match addr_res with
|
|
Some addr ->
|
|
` fstpl {emit_addressing addr i.arg pos_res}\n`
|
|
| None ->
|
|
` fstpl {emit_shift i.res.(0)}\n`
|
|
end
|
|
| Lreloadretaddr ->
|
|
()
|
|
| Lreturn ->
|
|
output_epilogue();
|
|
` ret\n`
|
|
| Llabel lbl ->
|
|
`{emit_label lbl}:\n`
|
|
| Lbranch lbl ->
|
|
` jmp {emit_label lbl}\n`
|
|
| Lcondbranch(tst, lbl) ->
|
|
begin match tst with
|
|
Itruetest ->
|
|
output_test_zero i.arg.(0);
|
|
` jne {emit_label lbl}\n`
|
|
| Ifalsetest ->
|
|
output_test_zero i.arg.(0);
|
|
` je {emit_label lbl}\n`
|
|
| Iinttest cmp ->
|
|
` cmpl {emit_reg i.arg.(1)}, {emit_reg i.arg.(0)}\n`;
|
|
let b = name_for_cond_branch cmp in
|
|
` j{emit_string b} {emit_label lbl}\n`
|
|
| Iinttest_imm((Isigned Ceq | Isigned Cne |
|
|
Iunsigned Ceq | Iunsigned Cne) as cmp, 0) ->
|
|
output_test_zero i.arg.(0);
|
|
let b = name_for_cond_branch cmp in
|
|
` j{emit_string b} {emit_label lbl}\n`
|
|
| Iinttest_imm(cmp, n) ->
|
|
` cmpl ${emit_int n}, {emit_reg i.arg.(0)}\n`;
|
|
let b = name_for_cond_branch cmp in
|
|
` j{emit_string b} {emit_label lbl}\n`
|
|
| Ifloattest cmp ->
|
|
` fldl {emit_reg i.arg.(0)}\n`;
|
|
let comp_instr =
|
|
match cmp with
|
|
Ceq | Cne -> "fucom"
|
|
| _ -> "fcom" in
|
|
begin match i.arg.(1).loc with
|
|
Stack s ->
|
|
` {emit_string comp_instr}pl {emit_shift i.arg.(1)}\n`
|
|
| _ ->
|
|
` {emit_string comp_instr}p {emit_shift i.arg.(1)}\n`
|
|
end;
|
|
` fnstsw %ax\n`;
|
|
begin match cmp with
|
|
Ceq ->
|
|
` andb $69, %ah\n`;
|
|
` cmpb $64, %ah\n`;
|
|
` je {emit_label lbl}\n`
|
|
| Cne ->
|
|
` andb $68, %ah\n`;
|
|
` xorb $64, %ah\n`;
|
|
` jne {emit_label lbl}\n`
|
|
| Cle ->
|
|
` andb $69, %ah\n`;
|
|
` decb %ah\n`;
|
|
` cmpb $64, %ah\n`;
|
|
` jb {emit_label lbl}\n`
|
|
| Cge ->
|
|
` andb $5, %ah\n`;
|
|
` je {emit_label lbl}\n`
|
|
| Clt ->
|
|
` andb $69, %ah\n`;
|
|
` cmpb $1, %ah\n`;
|
|
` je {emit_label lbl}\n`
|
|
| Cgt ->
|
|
` andb $69, %ah\n`;
|
|
` je {emit_label lbl}\n`
|
|
end
|
|
| Ioddtest ->
|
|
` testl $1, {emit_reg i.arg.(0)}\n`;
|
|
` jne {emit_label lbl}\n`
|
|
| Ieventest ->
|
|
` testl $1, {emit_reg i.arg.(0)}\n`;
|
|
` je {emit_label lbl}\n`
|
|
end
|
|
| Lcondbranch3(lbl0, lbl1, lbl2) ->
|
|
` cmpl $1, {emit_reg i.arg.(0)}\n`;
|
|
begin match lbl0 with
|
|
None -> ()
|
|
| Some lbl -> ` jb {emit_label lbl}\n`
|
|
end;
|
|
begin match lbl1 with
|
|
None -> ()
|
|
| Some lbl -> ` je {emit_label lbl}\n`
|
|
end;
|
|
begin match lbl2 with
|
|
None -> ()
|
|
| Some lbl -> ` jg {emit_label lbl}\n`
|
|
end
|
|
| Lswitch jumptbl ->
|
|
let lbl = new_label() in
|
|
` jmp *{emit_label lbl}(, {emit_reg i.arg.(0)}, 4)\n`;
|
|
emit_align 4;
|
|
`{emit_label lbl}:`;
|
|
for i = 0 to Array.length jumptbl - 1 do
|
|
` .long {emit_label jumptbl.(i)}\n`
|
|
done
|
|
| Lsetuptrap lbl ->
|
|
` call {emit_label lbl}\n`
|
|
| Lpushtrap ->
|
|
` pushl {emit_symbol "caml_exception_pointer"}\n`;
|
|
` movl %esp, {emit_symbol "caml_exception_pointer"}\n`;
|
|
stack_offset := !stack_offset + 8
|
|
| Lpoptrap ->
|
|
` popl {emit_symbol "caml_exception_pointer"}\n`;
|
|
` addl $4, %esp\n`;
|
|
stack_offset := !stack_offset - 8
|
|
| Lraise ->
|
|
` movl {emit_symbol "caml_exception_pointer"}, %esp\n`;
|
|
` popl {emit_symbol "caml_exception_pointer"}\n`;
|
|
` ret\n`
|
|
|
|
let rec emit_all i =
|
|
match i.desc with Lend -> () | _ -> emit_instr i; emit_all i.next
|
|
|
|
(* Emission of the floating-point constants *)
|
|
|
|
let emit_float_constant (lbl, cst) =
|
|
` .data\n`;
|
|
`{emit_label lbl}: .double {emit_string cst}\n`
|
|
|
|
(* Emission of a function declaration *)
|
|
|
|
let fundecl fundecl =
|
|
function_name := fundecl.fun_name;
|
|
fastcode_flag := fundecl.fun_fast;
|
|
tailrec_entry_point := new_label();
|
|
stack_offset := 0;
|
|
float_constants := [];
|
|
range_check_trap := 0;
|
|
` .text\n`;
|
|
emit_align 16; (* 16-byte alignment is recommended for the 486 *)
|
|
` .globl {emit_symbol fundecl.fun_name}\n`;
|
|
`{emit_symbol fundecl.fun_name}:\n`;
|
|
let n = frame_size() - 4 in
|
|
if n > 0 then
|
|
` subl ${emit_int n}, %esp\n`;
|
|
`{emit_label !tailrec_entry_point}:`;
|
|
emit_all fundecl.fun_body;
|
|
if !range_check_trap > 0 then
|
|
`{emit_label !range_check_trap}: int $5\n`;
|
|
List.iter emit_float_constant !float_constants
|
|
|
|
(* Emission of data *)
|
|
|
|
let emit_item = function
|
|
Cdefine_symbol s ->
|
|
` .globl {emit_symbol s}\n`;
|
|
`{emit_symbol s}:\n`
|
|
| Cdefine_label lbl ->
|
|
`{emit_label (10000 + lbl)}:\n`
|
|
| Cint8 n ->
|
|
` .byte {emit_int n}\n`
|
|
| Cint16 n ->
|
|
` .word {emit_int n}\n`
|
|
| Cint n ->
|
|
` .long {emit_int n}\n`
|
|
| Cintlit n ->
|
|
` .long {emit_string n}\n`
|
|
| Cfloat f ->
|
|
` .double {emit_string f}\n`
|
|
| Csymbol_address s ->
|
|
` .long {emit_symbol s}\n`
|
|
| Clabel_address lbl ->
|
|
` .long {emit_label (10000 + lbl)}\n`
|
|
| Cstring s ->
|
|
let l = String.length s in
|
|
if l = 0 then ()
|
|
else if l < 80 then
|
|
` .ascii {emit_string_literal s}\n`
|
|
else begin
|
|
let i = ref 0 in
|
|
while !i < l do
|
|
let n = min (l - !i) 80 in
|
|
` .ascii {emit_string_literal(String.sub s !i n)}\n`;
|
|
i := !i + n
|
|
done
|
|
end
|
|
| Cskip n ->
|
|
if n > 0 then ` .space {emit_int n}\n`
|
|
| Calign n ->
|
|
emit_align n
|
|
|
|
let data l =
|
|
` .data\n`;
|
|
List.iter emit_item l
|
|
|
|
(* Beginning / end of an assembly file *)
|
|
|
|
let begin_assembly() = ()
|
|
|
|
let end_assembly() =
|
|
let lbl = Compilenv.current_unit_name() ^ "_frametable" in
|
|
` .data\n`;
|
|
` .globl {emit_symbol lbl}\n`;
|
|
`{emit_symbol lbl}:\n`;
|
|
` .long {emit_int (List.length !frame_descriptors)}\n`;
|
|
List.iter emit_frame !frame_descriptors;
|
|
frame_descriptors := []
|