e_logf.s

Glibc 2.3.2源代码(解压后有100多M)

{ .mfb
     ldfd       log_T = [log_AD_2]
(p10) fmerge.s f8 = f0, f0
(p10) br.ret.spnt b0                // Exit for x=1.0
;;
}

{ .mfi
     getf.exp   log_GR_signexp_w = log_w
     fclass.m.unc p12,p0 = f8, 0x3a       // Test for x neg norm, unorm, inf
     nop.i 999
}
;;

{ .mmb
     nop.m 999
     nop.m 999
(p6) br.cond.spnt L(LOG_ZERO_NEG)      // Branch if x=0
;;
}
 

{ .mfi
     and log_GR_exp_w = log_GR_exp_17_ones, log_GR_signexp_w
     nop.f 999
     nop.i 999
}
{ .mfb
     nop.m 999
     fma.s1     log_rsq     = log_r, log_r, f0                   
(p12) br.cond.spnt L(LOG_ZERO_NEG)     // Branch if x<0
;;
}

{ .mfi
     nop.m 999
     fma.s1      log_rp_p32 = log_P3, log_r, log_P2
     nop.i 999
}
{ .mfi
     nop.m 999
     fma.s1    log_rp_q32   = log_P3, log_w, log_P2
     nop.i 999
;;
}

{ .mfi
     nop.m 999
     fcvt.xf   log_Nfloat = log_int_Nfloat
     nop.i 999 ;;
}

{ .mfi
     nop.m 999
     fma.s1    log_rp_p10   = log_P1, log_r, f1
     nop.i 999
}
{ .mfi
     nop.m 999
     fma.s1    log_rp_q10  = log_P1, log_w, f1
     nop.i 999
;;
}

//    p13 <== large w log
//    p14 <== small w log
{ .mfi
(p8) cmp.ge.unc p13,p14 = log_GR_exp_w, log_GR_fff7
     fcmp.eq.s0 p6,p0 = f8,f0         // Sets flag on +denormal input
     nop.i 999
;;
}

//    p10 <== large w log10
//    p11 <== small w log10
{ .mfi
(p7) cmp.ge.unc p10,p11 = log_GR_exp_w, log_GR_fff7
     nop.f 999
     nop.i 999 ;;
}

{ .mfi
     nop.m 999
     fma.s1        log_T_plus_Nlog2 = log_Nfloat,log_log2, log_T    
     nop.i 999 ;;
}


{ .mfi
     nop.m 999
     fma.s1     log_rp_p2   = log_rp_p32, log_rsq, log_rp_p10
     nop.i 999
}
{ .mfi
     nop.m 999
     fma.s1     log_rp_q2   = log_rp_q32, log_wsq, log_rp_q10
     nop.i 999
;;
}


//    small w, log   <== p14
{ .mfi
     nop.m 999
(p14) fma.s        f8       = log_rp_q2, log_w, f0
     nop.i 999
}
{ .mfi
     nop.m 999
(p11) fma.s1        log_Q       = log_rp_q2, log_w, f0
     nop.i 999 ;;
}


//    large w, log   <== p13
.pred.rel "mutex",p13,p10
{ .mfi
      nop.m 999
(p13) fma.s        f8        = log_rp_p2, log_r, log_T_plus_Nlog2
      nop.i 999 
}
{ .mfi
      nop.m 999
(p10) fma.s1     log_Q     = log_rp_p2, log_r, log_T_plus_Nlog2
      nop.i 999  ;;
}


//    log10
{ .mfb
      nop.m 999
(p7)  fma.s      f8 = log_inv_ln10,log_Q,f0                         
      br.ret.sptk     b0 
;;
}


L(LOG_DENORM):
{ .mmi
     getf.exp   log_GR_signexp_f8 = log_NORM_f8 
     nop.m 999
     nop.i 999
}
;;
{ .mmb
     getf.sig   log_GR_significand_f8 = log_NORM_f8 
     and        log_GR_exp_f8 = log_GR_signexp_f8, log_GR_exp_17_ones  
     br.cond.sptk L(LOG_COMMON)
}
;;

L(LOG_ZERO_NEG): 

// qnan snan inf norm     unorm 0 -+
// 0    0    0   0        0     1 11      0x7
// 0    0    1   1        1     0 10      0x3a

// Save x (f8) in f10
{ .mfi
     nop.m 999
     fmerge.s f10 = f8,f8 
     nop.i 999  ;;
}

// p8 p9  means  ln(+-0)  = -inf
// p7 p10 means  log(+-0) = -inf

//    p13 means  ln(-)
//    p14 means  log(-)


{ .mfi
     nop.m 999
     fmerge.ns   f6 = f1,f1            // Form -1.0
     nop.i 999  ;;
}

// p9  means  ln(+-0)  = -inf
// p10 means  log(+-0) = -inf
// Log(+-0) = -inf 

{ .mfi
	nop.m 999
(p8)  fclass.m.unc  p9,p0 = f10, 0x07           
	nop.i 999
}
{ .mfi
	nop.m 999
(p7)  fclass.m.unc  p10,p0 = f10, 0x07           
	nop.i 999 ;;
}


// p13  ln(-)
// p14  log(-)

// Log(-inf, -normal, -unnormal) = QNAN indefinite
{ .mfi
	nop.m 999
(p8)  fclass.m.unc  p13,p0 = f10, 0x3a           
	nop.i 999 
}
{ .mfi
	nop.m 999
(p7)  fclass.m.unc  p14,p0 = f10, 0x3a           
	nop.i 999  ;;
}


.pred.rel "mutex",p9,p10
{ .mfi
(p9)     mov        log_GR_tag = 4       
(p9)    frcpa f8,p11 = f6,f0                   
            nop.i 999
}
{ .mfi
(p10)    mov        log_GR_tag = 10       
(p10)   frcpa f8,p12 = f6,f0                   
            nop.i 999 ;;
}

.pred.rel "mutex",p13,p14
{ .mfi
(p13)    mov        log_GR_tag = 5       
(p13)    frcpa f8,p11 = f0,f0                   
            nop.i 999
}
{ .mfb
(p14)    mov        log_GR_tag = 11       
(p14)   frcpa f8,p12 = f0,f0                   
        br.cond.sptk __libm_error_region ;; 
}
.endp logf
ASM_SIZE_DIRECTIVE(logf)
ASM_SIZE_DIRECTIVE(__ieee754_logf)


// Stack operations when calling error support.
//       (1)               (2)                          (3) (call)              (4)
//   sp   -> +          psp -> +                     psp -> +                   sp -> +
//           |                 |                            |                         |
//           |                 | <- GR_Y               R3 ->| <- GR_RESULT            | -> f8
//           |                 |                            |                         |
//           | <-GR_Y      Y2->|                       Y2 ->| <- GR_Y                 |
//           |                 |                            |                         |
//           |                 | <- GR_X               X1 ->|                         |
//           |                 |                            |                         |
//  sp-64 -> +          sp ->  +                     sp ->  +                         +
//    save ar.pfs          save b0                                               restore gp
//    save gp                                                                    restore ar.pfs



.proc __libm_error_region
__libm_error_region:
.prologue

// (1)
{ .mfi
        add   GR_Parameter_Y=-32,sp             // Parameter 2 value
        nop.f 0
.save   ar.pfs,GR_SAVE_PFS
        mov  GR_SAVE_PFS=ar.pfs                 // Save ar.pfs
}
{ .mfi
.fframe 64
        add sp=-64,sp                          // Create new stack
        nop.f 0
        mov GR_SAVE_GP=gp                      // Save gp
};;


// (2)
{ .mmi
        stfs [GR_Parameter_Y] = f1,16         // STORE Parameter 2 on stack
        add GR_Parameter_X = 16,sp            // Parameter 1 address
.save   b0, GR_SAVE_B0
        mov GR_SAVE_B0=b0                     // Save b0
};;

.body
// (3)
{ .mib
        stfs [GR_Parameter_X] = f10                   // STORE Parameter 1 on stack
        add   GR_Parameter_RESULT = 0,GR_Parameter_Y  // Parameter 3 address
        nop.b 0                             
}
{ .mib
        stfs [GR_Parameter_Y] = f8                    // STORE Parameter 3 on stack
        add   GR_Parameter_Y = -16,GR_Parameter_Y
        br.call.sptk b0=__libm_error_support#         // Call error handling function
};;

{ .mmi
        nop.m 0
        nop.m 0
        add   GR_Parameter_RESULT = 48,sp
};;

// (4)
{ .mmi
        ldfs  f8 = [GR_Parameter_RESULT]       // Get return result off stack
.restore sp
        add   sp = 64,sp                       // Restore stack pointer
        mov   b0 = GR_SAVE_B0                  // Restore return address
};;
{ .mib
        mov   gp = GR_SAVE_GP                  // Restore gp
        mov   ar.pfs = GR_SAVE_PFS             // Restore ar.pfs
        br.ret.sptk     b0                     // Return
};;

.endp __libm_error_region
ASM_SIZE_DIRECTIVE(__libm_error_region)


.type   __libm_error_support#,@function
.global __libm_error_support#