src/assembly/x86-64/arith.lisp

   1 ;;;; simple cases for generic arithmetic
   2
   3 ;;;; This software is part of the SBCL system. See the README file for
   4 ;;;; more information.
   5 ;;;;
   6 ;;;; This software is derived from the CMU CL system, which was
   7 ;;;; written at Carnegie Mellon University and released into the
   8 ;;;; public domain. The software is in the public domain and is
   9 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
  10 ;;;; files for more information.
  11
  12 (in-package "SB!VM")
  13 \f
  14 ;;;; addition, subtraction, and multiplication
  15
  16 (macrolet ((define-generic-arith-routine ((fun cost) &body body)
  17              `(define-assembly-routine (,(symbolicate "GENERIC-" fun)
  18                                         (:cost ,cost)
  19                                         (:return-style :full-call)
  20                                         (:translate ,fun)
  21                                         (:policy :safe)
  22                                         (:save-p t))
  23                 ((:arg x (descriptor-reg any-reg) rdx-offset)
  24                  (:arg y (descriptor-reg any-reg)
  25                        ;; this seems wrong esi-offset -- FIXME: What's it mean?
  26                        rdi-offset)
  27
  28                  (:res res (descriptor-reg any-reg) rdx-offset)
  29
  30                  (:temp rax unsigned-reg rax-offset)
  31                  (:temp rcx unsigned-reg rcx-offset))
  32
  33                 (inst mov rcx x)
  34                 (inst or rcx y)
  35                 (inst test rcx fixnum-tag-mask) ; both fixnums?
  36                 (inst jmp :nz DO-STATIC-FUN)    ; no - do generic
  37
  38                 ,@body
  39                 (inst clc)
  40                 (inst ret)
  41
  42                 DO-STATIC-FUN
  43                 (inst pop rax)
  44                 (inst push rbp-tn)
  45                 (inst lea
  46                       rbp-tn
  47                       (make-ea :qword :base rsp-tn :disp n-word-bytes))
  48                 (inst sub rsp-tn (fixnumize 2))
  49                 (inst push rax)              ; callers return addr
  50                 (inst mov rcx (fixnumize 2)) ; arg count
  51                 (inst jmp
  52                       (make-ea :qword
  53                                :disp (+ nil-value
  54                                         (static-fun-offset
  55                                          ',(symbolicate "TWO-ARG-" fun))))))))
  56
  57   (define-generic-arith-routine (+ 10)
  58     (move res x)
  59     (inst add res y)
  60     (inst jmp :no OKAY)
  61     (inst rcr res 1)                  ; carry has correct sign
  62     (inst sar res 2)                  ; remove type bits
  63
  64     (move rcx res)
  65
  66     (with-fixed-allocation (res bignum-widetag (1+ bignum-digits-offset))
  67       (storew rcx res bignum-digits-offset other-pointer-lowtag))
  68
  69     OKAY)
  70
  71   (define-generic-arith-routine (- 10)
  72     (move res x)
  73     (inst sub res y)
  74     (inst jmp :no OKAY)
  75     (inst cmc)                        ; carry has correct sign now
  76     (inst rcr res 1)
  77     (inst sar res 2)                  ; remove type bits
  78
  79     (move rcx res)
  80
  81     (with-fixed-allocation (res bignum-widetag (1+ bignum-digits-offset))
  82       (storew rcx res bignum-digits-offset other-pointer-lowtag))
  83     OKAY)
  84
  85   (define-generic-arith-routine (* 30)
  86     (move rax x)                     ; must use eax for 64-bit result
  87     (inst sar rax n-fixnum-tag-bits) ; remove *8 fixnum bias
  88     (inst imul y)                    ; result in edx:eax
  89     (inst jmp :no OKAY)              ; still fixnum
  90
  91     (inst shrd rax x n-fixnum-tag-bits) ; high bits from edx
  92     (inst sar x n-fixnum-tag-bits)      ; now shift edx too
  93
  94     (move rcx x)                   ; save high bits from cqo
  95     (inst cqo)                     ; edx:eax <- sign-extend of eax
  96     (inst cmp x rcx)
  97     (inst jmp :e SINGLE-WORD-BIGNUM)
  98
  99     (with-fixed-allocation (res bignum-widetag (+ bignum-digits-offset 2))
 100       (storew rax res bignum-digits-offset other-pointer-lowtag)
 101       (storew rcx res (1+ bignum-digits-offset) other-pointer-lowtag))
 102     (inst jmp DONE)
 103
 104     SINGLE-WORD-BIGNUM
 105
 106     (with-fixed-allocation (res bignum-widetag (1+ bignum-digits-offset))
 107       (storew rax res bignum-digits-offset other-pointer-lowtag))
 108     (inst jmp DONE)
 109
 110     OKAY
 111     (move res rax)
 112     DONE))
 113 \f
 114 ;;;; negation
 115
 116 (define-assembly-routine (generic-negate
 117                           (:cost 10)
 118                           (:return-style :full-call)
 119                           (:policy :safe)
 120                           (:translate %negate)
 121                           (:save-p t))
 122                          ((:arg x (descriptor-reg any-reg) rdx-offset)
 123                           (:res res (descriptor-reg any-reg) rdx-offset)
 124
 125                           (:temp rax unsigned-reg rax-offset)
 126                           (:temp rcx unsigned-reg rcx-offset))
 127   (inst test x fixnum-tag-mask)
 128   (inst jmp :z FIXNUM)
 129
 130   (inst pop rax)
 131   (inst push rbp-tn)
 132   (inst lea rbp-tn (make-ea :qword :base rsp-tn :disp n-word-bytes))
 133   (inst sub rsp-tn (fixnumize 2))
 134   (inst push rax)
 135   (inst mov rcx (fixnumize 1))    ; arg count
 136   (inst jmp (make-ea :qword
 137                      :disp (+ nil-value (static-fun-offset '%negate))))
 138
 139   FIXNUM
 140   (move res x)
 141   (inst neg res)                        ; (- most-negative-fixnum) is BIGNUM
 142   (inst jmp :no OKAY)
 143   (inst shr res n-fixnum-tag-bits)      ; sign bit is data - remove type bits
 144   (move rcx res)
 145
 146   (with-fixed-allocation (res bignum-widetag (1+ bignum-digits-offset))
 147     (storew rcx res bignum-digits-offset other-pointer-lowtag))
 148
 149   OKAY)
 150 \f
 151 ;;;; comparison
 152
 153 (macrolet ((define-cond-assem-rtn (name translate static-fn test)
 154              `(define-assembly-routine (,name
 155                                         (:cost 10)
 156                                         (:return-style :full-call)
 157                                         (:policy :safe)
 158                                         (:translate ,translate)
 159                                         (:save-p t))
 160                 ((:arg x (descriptor-reg any-reg) rdx-offset)
 161                  (:arg y (descriptor-reg any-reg) rdi-offset)
 162
 163                  (:res res descriptor-reg rdx-offset)
 164
 165                  (:temp eax unsigned-reg rax-offset)
 166                  (:temp ecx unsigned-reg rcx-offset))
 167
 168                 (inst mov ecx x)
 169                 (inst or ecx y)
 170                 (inst test ecx fixnum-tag-mask)
 171                 (inst jmp :nz DO-STATIC-FUN)
 172
 173                 (inst cmp x y)
 174                 (load-symbol res t)
 175                 (inst mov eax nil-value)
 176                 (inst cmov ,test res eax)
 177                 (inst clc)   ; single-value return
 178                 (inst ret)
 179
 180                 DO-STATIC-FUN
 181                 (inst pop eax)
 182                 (inst push rbp-tn)
 183                 (inst lea rbp-tn (make-ea :qword
 184                                           :base rsp-tn
 185                                           :disp n-word-bytes))
 186                 (inst sub rsp-tn (fixnumize 2)) ; FIXME: Push 2 words on stack,
 187                                                 ; weirdly?
 188                 (inst push eax)
 189                 (inst mov ecx (fixnumize 2)) ; FIXME: FIXNUMIZE and
 190                                         ; SINGLE-FLOAT-BITS are parallel,
 191                                         ; should be named parallelly.
 192                 (inst jmp (make-ea :qword
 193                                    :disp (+ nil-value
 194                                             (static-fun-offset ',static-fn)))))))
 195
 196   (define-cond-assem-rtn generic-< < two-arg-< :ge)
 197   (define-cond-assem-rtn generic-> > two-arg-> :le))
 198
 199 (define-assembly-routine (generic-eql
 200                           (:cost 10)
 201                           (:return-style :full-call)
 202                           (:policy :safe)
 203                           (:translate eql)
 204                           (:save-p t))
 205                          ((:arg x (descriptor-reg any-reg) rdx-offset)
 206                           (:arg y (descriptor-reg any-reg) rdi-offset)
 207
 208                           (:res res descriptor-reg rdx-offset)
 209
 210                           (:temp rax unsigned-reg rax-offset)
 211                           (:temp rcx unsigned-reg rcx-offset))
 212   (inst mov rcx x)
 213   (inst and rcx y)
 214   (inst test rcx fixnum-tag-mask)
 215   (inst jmp :nz DO-STATIC-FUN)
 216
 217   ;; At least one fixnum
 218   (inst cmp x y)
 219   (load-symbol res t)
 220   (inst mov rax nil-value)
 221   (inst cmov :ne res rax)
 222   (inst clc)
 223   (inst ret)
 224
 225   DO-STATIC-FUN
 226   (inst pop rax)
 227   (inst push rbp-tn)
 228   (inst lea rbp-tn (make-ea :qword :base rsp-tn :disp n-word-bytes))
 229   (inst sub rsp-tn (fixnumize 2))
 230   (inst push rax)
 231   (inst mov rcx (fixnumize 2))
 232   (inst jmp (make-ea :qword
 233                      :disp (+ nil-value (static-fun-offset 'eql)))))
 234
 235 (define-assembly-routine (generic-=
 236                           (:cost 10)
 237                           (:return-style :full-call)
 238                           (:policy :safe)
 239                           (:translate =)
 240                           (:save-p t))
 241                          ((:arg x (descriptor-reg any-reg) rdx-offset)
 242                           (:arg y (descriptor-reg any-reg) rdi-offset)
 243
 244                           (:res res descriptor-reg rdx-offset)
 245
 246                           (:temp rax unsigned-reg rax-offset)
 247                           (:temp rcx unsigned-reg rcx-offset))
 248   (inst mov rcx x)
 249   (inst or rcx y)
 250   (inst test rcx fixnum-tag-mask)
 251   (inst jmp :nz DO-STATIC-FUN)
 252
 253   ;; Both fixnums
 254   (inst cmp x y)
 255   (load-symbol res t)
 256   (inst mov rax nil-value)
 257   (inst cmov :ne res rax)
 258   (inst clc)
 259   (inst ret)
 260
 261   DO-STATIC-FUN
 262   (inst pop rax)
 263   (inst push rbp-tn)
 264   (inst lea rbp-tn (make-ea :qword :base rsp-tn :disp n-word-bytes))
 265   (inst sub rsp-tn (fixnumize 2))
 266   (inst push rax)
 267   (inst mov rcx (fixnumize 2))
 268   (inst jmp (make-ea :qword
 269                      :disp (+ nil-value (static-fun-offset 'two-arg-=)))))
 270
 271