! Copyright (C) 2005, 2008 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors assocs alien alien.c-types arrays strings
cpu.x86.assembler cpu.x86.assembler.private cpu.architecture
kernel kernel.private math memory namespaces make sequences
words system layouts combinators math.order fry locals
compiler.constants
compiler.cfg.registers
compiler.cfg.instructions
compiler.cfg.intrinsics
compiler.cfg.comparisons
compiler.cfg.stack-frame
compiler.codegen
compiler.codegen.fixup ;
IN: cpu.x86

<< enable-fixnum-log2 >>

! Add some methods to the assembler to be more useful to the backend
M: label JMP 0 JMP rc-relative label-fixup ;
M: label JUMPcc [ 0 ] dip JUMPcc rc-relative label-fixup ;

M: x86 two-operand? t ;

HOOK: stack-reg cpu ( -- reg )

HOOK: reserved-area-size cpu ( -- n )

: stack@ ( n -- op ) stack-reg swap [+] ;

: param@ ( n -- op ) reserved-area-size + stack@ ;

: spill-integer@ ( n -- op ) spill-integer-offset param@ ;

: spill-float@ ( n -- op ) spill-float-offset param@ ;

: gc-root@ ( n -- op ) gc-root-offset param@ ;

: decr-stack-reg ( n -- )
    dup 0 = [ drop ] [ stack-reg swap SUB ] if ;

: incr-stack-reg ( n -- )
    dup 0 = [ drop ] [ stack-reg swap ADD ] if ;

: align-stack ( n -- n' )
    os macosx? cpu x86.64? or [ 16 align ] when ;

M: x86 stack-frame-size ( stack-frame -- i )
    (stack-frame-size) 3 cells reserved-area-size + + align-stack ;

HOOK: temp-reg-1 cpu ( -- reg )
HOOK: temp-reg-2 cpu ( -- reg )

HOOK: param-reg-1 cpu ( -- reg )
HOOK: param-reg-2 cpu ( -- reg )

HOOK: pic-tail-reg cpu ( -- reg )

M: x86 %load-immediate MOV ;

M: x86 %load-reference swap 0 MOV rc-absolute-cell rel-immediate ;

HOOK: ds-reg cpu ( -- reg )
HOOK: rs-reg cpu ( -- reg )

: reg-stack ( n reg -- op ) swap cells neg [+] ;

GENERIC: loc>operand ( loc -- operand )

M: ds-loc loc>operand n>> ds-reg reg-stack ;
M: rs-loc loc>operand n>> rs-reg reg-stack ;

M: x86 %peek loc>operand MOV ;
M: x86 %replace loc>operand swap MOV ;
: (%inc) ( n reg -- ) swap cells dup 0 > [ ADD ] [ neg SUB ] if ; inline
M: x86 %inc-d ( n -- ) ds-reg (%inc) ;
M: x86 %inc-r ( n -- ) rs-reg (%inc) ;

M: x86 %call ( word -- ) 0 CALL rc-relative rel-word-pic ;

: xt-tail-pic-offset ( -- n )
    #! See the comment in vm/cpu-x86.hpp
    cell 4 + 1 + ; inline

M: x86 %jump ( word -- )
    pic-tail-reg 0 MOV xt-tail-pic-offset rc-absolute-cell rel-here
    0 JMP rc-relative rel-word-pic-tail ;

M: x86 %jump-label ( label -- ) 0 JMP rc-relative label-fixup ;

M: x86 %return ( -- ) 0 RET ;

: code-alignment ( align -- n )
    [ building get length dup ] dip align swap - ;

: align-code ( n -- )
    0 <repetition> % ;

:: (%slot) ( obj slot tag temp -- op )
    temp slot obj [+] LEA
    temp tag neg [+] ; inline

:: (%slot-imm) ( obj slot tag -- op )
    obj slot cells tag - [+] ; inline

M: x86 %slot ( dst obj slot tag temp -- ) (%slot) MOV ;
M: x86 %slot-imm ( dst obj slot tag -- ) (%slot-imm) MOV ;
M: x86 %set-slot ( src obj slot tag temp -- ) (%slot) swap MOV ;
M: x86 %set-slot-imm ( src obj slot tag -- ) (%slot-imm) swap MOV ;

M: x86 %add     [+] LEA ;
M: x86 %add-imm [+] LEA ;
M: x86 %sub     nip SUB ;
M: x86 %sub-imm neg [+] LEA ;
M: x86 %mul     nip swap IMUL2 ;
M: x86 %mul-imm IMUL3 ;
M: x86 %and     nip AND ;
M: x86 %and-imm nip AND ;
M: x86 %or      nip OR ;
M: x86 %or-imm  nip OR ;
M: x86 %xor     nip XOR ;
M: x86 %xor-imm nip XOR ;
M: x86 %shl-imm nip SHL ;
M: x86 %shr-imm nip SHR ;
M: x86 %sar-imm nip SAR ;
M: x86 %not     drop NOT ;
M: x86 %log2    BSR ;

: ?MOV ( dst src -- )
    2dup = [ 2drop ] [ MOV ] if ; inline

:: move>args ( src1 src2 -- )
    {
        { [ src1 param-reg-2 = ] [ param-reg-1 src2 ?MOV param-reg-1 param-reg-2 XCHG ] }
        { [ src1 param-reg-1 = ] [ param-reg-2 src2 ?MOV ] }
        { [ src2 param-reg-1 = ] [ param-reg-2 src1 ?MOV param-reg-1 param-reg-2 XCHG ] }
        { [ src2 param-reg-2 = ] [ param-reg-1 src1 ?MOV ] }
        [
            param-reg-1 src1 MOV
            param-reg-2 src2 MOV
        ]
    } cond ;

HOOK: %alien-invoke-tail cpu ( func dll -- )

:: overflow-template ( src1 src2 insn inverse func -- )
    <label> "no-overflow" set
    src1 src2 insn call
    ds-reg [] src1 MOV
    "no-overflow" get JNO
    src1 src2 inverse call
    src1 src2 move>args
    %prepare-alien-invoke
    func f %alien-invoke
    "no-overflow" resolve-label ; inline

:: overflow-template-tail ( src1 src2 insn inverse func -- )
    <label> "no-overflow" set
    src1 src2 insn call
    "no-overflow" get JNO
    src1 src2 inverse call
    src1 src2 move>args
    %prepare-alien-invoke
    func f %alien-invoke-tail
    "no-overflow" resolve-label
    ds-reg [] src1 MOV
    0 RET ; inline

M: x86 %fixnum-add ( src1 src2 -- )
    [ ADD ] [ SUB ] "overflow_fixnum_add" overflow-template ;

M: x86 %fixnum-add-tail ( src1 src2 -- )
    [ ADD ] [ SUB ] "overflow_fixnum_add" overflow-template-tail ;

M: x86 %fixnum-sub ( src1 src2 -- )
    [ SUB ] [ ADD ] "overflow_fixnum_subtract" overflow-template ;

M: x86 %fixnum-sub-tail ( src1 src2 -- )
    [ SUB ] [ ADD ] "overflow_fixnum_subtract" overflow-template-tail ;

M:: x86 %fixnum-mul ( src1 src2 temp1 temp2 -- )
    "no-overflow" define-label
    temp1 src1 MOV
    temp1 tag-bits get SAR
    src2 temp1 IMUL2
    ds-reg [] temp1 MOV
    "no-overflow" get JNO
    src1 src2 move>args
    param-reg-1 tag-bits get SAR
    param-reg-2 tag-bits get SAR
    %prepare-alien-invoke
    "overflow_fixnum_multiply" f %alien-invoke
    "no-overflow" resolve-label ;

M:: x86 %fixnum-mul-tail ( src1 src2 temp1 temp2 -- )
    "overflow" define-label
    temp1 src1 MOV
    temp1 tag-bits get SAR
    src2 temp1 IMUL2
    "overflow" get JO
    ds-reg [] temp1 MOV
    0 RET
    "overflow" resolve-label
    src1 src2 move>args
    param-reg-1 tag-bits get SAR
    param-reg-2 tag-bits get SAR
    %prepare-alien-invoke
    "overflow_fixnum_multiply" f %alien-invoke-tail ;

: bignum@ ( reg n -- op )
    cells bignum tag-number - [+] ; inline

M:: x86 %integer>bignum ( dst src temp -- )
    #! on entry, inreg is a signed 32-bit quantity
    #! exits with tagged ptr to bignum in outreg
    #! 1 cell header, 1 cell length, 1 cell sign, + digits
    #! length is the # of digits + sign
    [
        "end" define-label
        ! Load cached zero value
        dst 0 >bignum %load-reference
        src 0 CMP
        ! Is it zero? Then just go to the end and return this zero
        "end" get JE
        ! Allocate a bignum
        dst 4 cells bignum temp %allot
        ! Write length
        dst 1 bignum@ 2 tag-fixnum MOV
        ! Store value
        dst 3 bignum@ src MOV
        ! Compute sign
        temp src MOV
        temp cell-bits 1- SAR
        temp 1 AND
        ! Store sign
        dst 2 bignum@ temp MOV
        ! Make negative value positive
        temp temp ADD
        temp NEG
        temp 1 ADD
        src temp IMUL2
        ! Store the bignum
        dst 3 bignum@ temp MOV
        "end" resolve-label
    ] with-scope ;

M:: x86 %bignum>integer ( dst src temp -- )
    [
        "end" define-label
        ! load length
        temp src 1 bignum@ MOV
        ! if the length is 1, its just the sign and nothing else,
        ! so output 0
        dst 0 MOV
        temp 1 tag-fixnum CMP
        "end" get JE
        ! load the value
        dst src 3 bignum@ MOV
        ! load the sign
        temp src 2 bignum@ MOV
        ! convert it into -1 or 1
        temp temp ADD
        temp NEG
        temp 1 ADD
        ! make dst signed
        temp dst IMUL2
        "end" resolve-label
    ] with-scope ;

M: x86 %add-float nip ADDSD ;
M: x86 %sub-float nip SUBSD ;
M: x86 %mul-float nip MULSD ;
M: x86 %div-float nip DIVSD ;

M: x86 %integer>float CVTSI2SD ;
M: x86 %float>integer CVTTSD2SI ;

M: x86 %copy ( dst src -- ) ?MOV ;

M: x86 %copy-float ( dst src -- )
    2dup = [ 2drop ] [ MOVSD ] if ;

M: x86 %unbox-float ( dst src -- )
    float-offset [+] MOVSD ;

M:: x86 %unbox-any-c-ptr ( dst src temp -- )
    [
        { "is-byte-array" "end" "start" } [ define-label ] each
        dst 0 MOV
        temp src MOV
        ! We come back here with displaced aliens
        "start" resolve-label
        ! Is the object f?
        temp \ f tag-number CMP
        "end" get JE
        ! Is the object an alien?
        temp header-offset [+] alien type-number tag-fixnum CMP
        "is-byte-array" get JNE
        ! If so, load the offset and add it to the address
        dst temp alien-offset [+] ADD
        ! Now recurse on the underlying alien
        temp temp underlying-alien-offset [+] MOV
        "start" get JMP
        "is-byte-array" resolve-label
        ! Add byte array address to address being computed
        dst temp ADD
        ! Add an offset to start of byte array's data
        dst byte-array-offset ADD
        "end" resolve-label
    ] with-scope ;

M:: x86 %box-float ( dst src temp -- )
    dst 16 float temp %allot
    dst float-offset [+] src MOVSD ;

: alien@ ( reg n -- op ) cells alien tag-number - [+] ;

M:: x86 %box-alien ( dst src temp -- )
    [
        "end" define-label
        dst \ f tag-number MOV
        src 0 CMP
        "end" get JE
        dst 4 cells alien temp %allot
        dst 1 alien@ \ f tag-number MOV
        dst 2 alien@ \ f tag-number MOV
        ! Store src in alien-offset slot
        dst 3 alien@ src MOV
        "end" resolve-label
    ] with-scope ;

: small-reg-8 ( reg -- reg' )
    H{
        { EAX RAX }
        { ECX RCX }
        { EDX RDX }
        { EBX RBX }
        { ESP RSP }
        { EBP RBP }
        { ESI RSP }
        { EDI RDI }

        { RAX RAX }
        { RCX RCX }
        { RDX RDX }
        { RBX RBX }
        { RSP RSP }
        { RBP RBP }
        { RSI RSP }
        { RDI RDI }
    } at ; inline

: small-reg-4 ( reg -- reg' )
    small-reg-8 H{
        { RAX EAX }
        { RCX ECX }
        { RDX EDX }
        { RBX EBX }
        { RSP ESP }
        { RBP EBP }
        { RSI ESP }
        { RDI EDI }
    } at ; inline

: small-reg-2 ( reg -- reg' )
    small-reg-4 H{
        { EAX AX }
        { ECX CX }
        { EDX DX }
        { EBX BX }
        { ESP SP }
        { EBP BP }
        { ESI SI }
        { EDI DI }
    } at ; inline

: small-reg-1 ( reg -- reg' )
    small-reg-4 {
        { EAX AL }
        { ECX CL }
        { EDX DL }
        { EBX BL }
    } at ; inline

: small-reg ( reg size -- reg' )
    {
        { 1 [ small-reg-1 ] }
        { 2 [ small-reg-2 ] }
        { 4 [ small-reg-4 ] }
        { 8 [ small-reg-8 ] }
    } case ;

HOOK: small-regs cpu ( -- regs )

M: x86.32 small-regs { EAX ECX EDX EBX } ;
M: x86.64 small-regs { RAX RCX RDX RBX } ;

HOOK: small-reg-native cpu ( reg -- reg' )

M: x86.32 small-reg-native small-reg-4 ;
M: x86.64 small-reg-native small-reg-8 ;

: small-reg-that-isn't ( exclude -- reg' )
    small-regs swap [ small-reg-native ] map '[ _ memq? not ] find nip ;

: with-save/restore ( reg quot -- )
    [ drop PUSH ] [ call ] [ drop POP ] 2tri ; inline

:: with-small-register ( dst exclude quot: ( new-dst -- ) -- )
    #! If the destination register overlaps a small register, we
    #! call the quot with that. Otherwise, we find a small
    #! register that is not in exclude, and call quot, saving
    #! and restoring the small register.
    dst small-reg-native small-regs memq? [ dst quot call ] [
        exclude small-reg-that-isn't
        [ quot call ] with-save/restore
    ] if ; inline

M:: x86 %string-nth ( dst src index temp -- )
    "end" define-label
    dst { src index temp } [| new-dst |
        ! Load the least significant 7 bits into new-dst.
        ! 8th bit indicates whether we have to load from
        ! the aux vector or not.
        temp src index [+] LEA
        new-dst 1 small-reg temp string-offset [+] MOV
        new-dst new-dst 1 small-reg MOVZX
        ! Do we have to look at the aux vector?
        new-dst HEX: 80 CMP
        "end" get JL
        ! Yes, this is a non-ASCII character. Load aux vector
        temp src string-aux-offset [+] MOV
        new-dst temp XCHG
        ! Compute index
        new-dst index ADD
        new-dst index ADD
        ! Load high 16 bits
        new-dst 2 small-reg new-dst byte-array-offset [+] MOV
        new-dst new-dst 2 small-reg MOVZX
        new-dst 7 SHL
        ! Compute code point
        new-dst temp XOR
        "end" resolve-label
        dst new-dst ?MOV
    ] with-small-register ;

M:: x86 %set-string-nth-fast ( ch str index temp -- )
    ch { index str temp } [| new-ch |
        new-ch ch ?MOV
        temp str index [+] LEA
        temp string-offset [+] new-ch 1 small-reg MOV
    ] with-small-register ;

:: %alien-integer-getter ( dst src size quot -- )
    dst { src } [| new-dst |
        new-dst dup size small-reg dup src [] MOV
        quot call
        dst new-dst ?MOV
    ] with-small-register ; inline

: %alien-unsigned-getter ( dst src size -- )
    [ MOVZX ] %alien-integer-getter ; inline

M: x86 %alien-unsigned-1 1 %alien-unsigned-getter ;
M: x86 %alien-unsigned-2 2 %alien-unsigned-getter ;

: %alien-signed-getter ( dst src size -- )
    [ MOVSX ] %alien-integer-getter ; inline

M: x86 %alien-signed-1 1 %alien-signed-getter ;
M: x86 %alien-signed-2 2 %alien-signed-getter ;
M: x86 %alien-signed-4 4 %alien-signed-getter ;

M: x86 %alien-unsigned-4 4 [ 2drop ] %alien-integer-getter ;

M: x86 %alien-cell [] MOV ;
M: x86 %alien-float dupd [] MOVSS dup CVTSS2SD ;
M: x86 %alien-double [] MOVSD ;

:: %alien-integer-setter ( ptr value size -- )
    value { ptr } [| new-value |
        new-value value ?MOV
        ptr [] new-value size small-reg MOV
    ] with-small-register ; inline

M: x86 %set-alien-integer-1 1 %alien-integer-setter ;
M: x86 %set-alien-integer-2 2 %alien-integer-setter ;
M: x86 %set-alien-integer-4 4 %alien-integer-setter ;
M: x86 %set-alien-cell [ [] ] dip MOV ;
M: x86 %set-alien-float dup dup CVTSD2SS [ [] ] dip MOVSS ;
M: x86 %set-alien-double [ [] ] dip MOVSD ;

: load-zone-ptr ( reg -- )
    #! Load pointer to start of zone array
    0 MOV "nursery" f rc-absolute-cell rel-dlsym ;

: load-allot-ptr ( nursery-ptr allot-ptr -- )
    [ drop load-zone-ptr ] [ swap cell [+] MOV ] 2bi ;

: inc-allot-ptr ( nursery-ptr n -- )
    [ cell [+] ] dip 8 align ADD ;

: store-header ( temp class -- )
    [ [] ] [ type-number tag-fixnum ] bi* MOV ;

: store-tagged ( dst tag -- )
    tag-number OR ;

M:: x86 %allot ( dst size class nursery-ptr -- )
    nursery-ptr dst load-allot-ptr
    dst class store-header
    dst class store-tagged
    nursery-ptr size inc-allot-ptr ;

M:: x86 %write-barrier ( src card# table -- )
    #! Mark the card pointed to by vreg.
    ! Mark the card
    card# src MOV
    card# card-bits SHR
    table "cards_offset" f %alien-global
    table table [] MOV
    table card# [+] card-mark <byte> MOV

    ! Mark the card deck
    card# deck-bits card-bits - SHR
    table "decks_offset" f %alien-global
    table table [] MOV
    table card# [+] card-mark <byte> MOV ;

:: check-nursery ( temp1 temp2 -- )
    temp1 load-zone-ptr
    temp2 temp1 cell [+] MOV
    temp2 1024 ADD
    temp1 temp1 3 cells [+] MOV
    temp2 temp1 CMP ;

GENERIC# save-gc-root 1 ( gc-root operand temp -- )

M:: spill-slot save-gc-root ( gc-root spill-slot temp -- )
    temp spill-slot n>> spill-integer@ MOV
    gc-root gc-root@ temp MOV ;

M:: word save-gc-root ( gc-root register temp -- )
    gc-root gc-root@ register MOV ;

: save-gc-roots ( gc-roots temp -- )
    '[ _ save-gc-root ] assoc-each ;

GENERIC# load-gc-root 1 ( gc-root operand temp -- )

M:: spill-slot load-gc-root ( gc-root spill-slot temp -- )
    temp gc-root gc-root@ MOV
    spill-slot n>> spill-integer@ temp MOV ;

M:: word load-gc-root ( gc-root register temp -- )
    register gc-root gc-root@ MOV ;

: load-gc-roots ( gc-roots temp -- )
    '[ _ load-gc-root ] assoc-each ;

:: call-gc ( gc-root-count -- )
    ! Pass pointer to start of GC roots as first parameter
    param-reg-1 gc-root-base param@ LEA
    ! Pass number of roots as second parameter
    param-reg-2 gc-root-count MOV
    ! Call GC
    %prepare-alien-invoke
    "inline_gc" f %alien-invoke ;

M:: x86 %gc ( temp1 temp2 gc-roots gc-root-count -- )
    "end" define-label
    temp1 temp2 check-nursery
    "end" get JLE
    gc-roots temp1 save-gc-roots
    gc-root-count call-gc
    gc-roots temp1 load-gc-roots
    "end" resolve-label ;

M: x86 %alien-global
    [ 0 MOV ] 2dip rc-absolute-cell rel-dlsym ;

M: x86 %epilogue ( n -- ) cell - incr-stack-reg ;

:: %boolean ( dst temp word -- )
    dst \ f tag-number MOV
    temp 0 MOV \ t rc-absolute-cell rel-immediate
    dst temp word execute ; inline

M: x86 %compare ( dst temp cc src1 src2 -- )
    CMP {
        { cc< [ \ CMOVL %boolean ] }
        { cc<= [ \ CMOVLE %boolean ] }
        { cc> [ \ CMOVG %boolean ] }
        { cc>= [ \ CMOVGE %boolean ] }
        { cc= [ \ CMOVE %boolean ] }
        { cc/= [ \ CMOVNE %boolean ] }
    } case ;

M: x86 %compare-imm ( dst temp cc src1 src2 -- )
    %compare ;

M: x86 %compare-float ( dst temp cc src1 src2 -- )
    UCOMISD {
        { cc< [ \ CMOVB %boolean ] }
        { cc<= [ \ CMOVBE %boolean ] }
        { cc> [ \ CMOVA %boolean ] }
        { cc>= [ \ CMOVAE %boolean ] }
        { cc= [ \ CMOVE %boolean ] }
        { cc/= [ \ CMOVNE %boolean ] }
    } case ;

M: x86 %compare-branch ( label cc src1 src2 -- )
    CMP {
        { cc< [ JL ] }
        { cc<= [ JLE ] }
        { cc> [ JG ] }
        { cc>= [ JGE ] }
        { cc= [ JE ] }
        { cc/= [ JNE ] }
    } case ;

M: x86 %compare-imm-branch ( label src1 src2 cc -- )
    %compare-branch ;

M: x86 %compare-float-branch ( label cc src1 src2 -- )
    UCOMISD {
        { cc< [ JB ] }
        { cc<= [ JBE ] }
        { cc> [ JA ] }
        { cc>= [ JAE ] }
        { cc= [ JE ] }
        { cc/= [ JNE ] }
    } case ;

M: x86 %spill-integer ( src n -- ) spill-integer@ swap MOV ;
M: x86 %reload-integer ( dst n -- ) spill-integer@ MOV ;

M: x86 %spill-float ( src n -- ) spill-float@ swap MOVSD ;
M: x86 %reload-float ( dst n -- ) spill-float@ MOVSD ;

M: x86 %loop-entry 16 code-alignment [ NOP ] times ;

M: int-regs %save-param-reg drop [ param@ ] dip MOV ;
M: int-regs %load-param-reg drop swap param@ MOV ;

GENERIC: MOVSS/D ( dst src reg-class -- )

M: single-float-regs MOVSS/D drop MOVSS ;
M: double-float-regs MOVSS/D drop MOVSD ;

M: float-regs %save-param-reg [ param@ ] 2dip MOVSS/D ;
M: float-regs %load-param-reg [ swap param@ ] dip MOVSS/D ;

GENERIC: push-return-reg ( reg-class -- )
GENERIC: load-return-reg ( n reg-class -- )
GENERIC: store-return-reg ( n reg-class -- )

M: x86 %prepare-alien-invoke
    #! Save Factor stack pointers in case the C code calls a
    #! callback which does a GC, which must reliably trace
    #! all roots.
    temp-reg-1 "stack_chain" f %alien-global
    temp-reg-1 temp-reg-1 [] MOV
    temp-reg-1 [] stack-reg MOV
    temp-reg-1 [] cell SUB
    temp-reg-1 2 cells [+] ds-reg MOV
    temp-reg-1 3 cells [+] rs-reg MOV ;

M: x86 value-struct? drop t ;

M: x86 small-enough? ( n -- ? )
    HEX: -80000000 HEX: 7fffffff between? ;

: next-stack@ ( n -- operand )
    #! nth parameter from the next stack frame. Used to box
    #! input values to callbacks; the callback has its own
    #! stack frame set up, and we want to read the frame
    #! set up by the caller.
    stack-frame get total-size>> + stack@ ;