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-rw-r--r--sysdeps/ia64/fpu/s_logbl.S311
1 files changed, 146 insertions, 165 deletions
diff --git a/sysdeps/ia64/fpu/s_logbl.S b/sysdeps/ia64/fpu/s_logbl.S
index 38b131f3aa..6a08e94201 100644
--- a/sysdeps/ia64/fpu/s_logbl.S
+++ b/sysdeps/ia64/fpu/s_logbl.S
@@ -1,10 +1,10 @@
 .file "logbl.s"
 
-// Copyright (C) 2000, 2001, Intel Corporation
+
+// Copyright (c) 2000 - 2003, Intel Corporation
 // All rights reserved.
-// 
-// Contributed 2/2/2000 by John Harrison, Ted Kubaska, Bob Norin, Shane Story,
-// and Ping Tak Peter Tang of the Computational Software Lab, Intel Corporation.
+//
+// Contributed 2000 by the Intel Numerics Group, Intel Corporation
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
@@ -20,44 +20,46 @@
 // * The name of Intel Corporation may not be used to endorse or promote
 // products derived from this software without specific prior written
 // permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
+
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS 
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS
 // CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
-// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
-// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
-// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 
+// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 // OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY OR TORT (INCLUDING
-// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
-// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
-// 
+// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
 // Intel Corporation is the author of this code, and requests that all
-// problem reports or change requests be submitted to it directly at 
-// http://developer.intel.com/opensource.
+// problem reports or change requests be submitted to it directly at
+// http://www.intel.com/software/products/opensource/libraries/num.htm.
 //
 // History
 //==============================================================
-// 2/02/00  Initial version
-// 2/16/00  Modified to conform to C9X 
-// 3/16/00  Improved speed
-// 4/04/00  Unwind support added
-// 5/30/00  Fixed bug when x double-extended denormal
-// 8/15/00  Bundle added after call to __libm_error_support to properly
+// 02/02/00 Initial version
+// 02/16/00 Modified to conform to C9X
+// 03/16/00 Improved speed
+// 04/04/00 Unwind support added
+// 05/30/00 Fixed bug when x double-extended denormal
+// 08/15/00 Bundle added after call to __libm_error_support to properly
 //          set [the previously overwritten] GR_Parameter_RESULT.
+// 05/20/02 Cleaned up namespace and sf0 syntax
+// 01/20/03 Improved performance
 //
 // API
 //==============================================================
-// long double logbl( long double x);
+// long double logbl( long double x );
 //
 // Overview of operation
 //==============================================================
-// The logbl function extracts the exponent of x as an integer in 
-// floating-point format. 
+// The logbl function extracts the exponent of x as an integer in
+// floating-point format.
 // logbl computes log2 of x as a long double
 //
-// logbl is similar to ilogbl but differs in the  following ways:
+// logbl is similar to ilogbl but differs in the following ways:
 //         +-inf
 //            ilogbl: returns INT_MAX
 //             logbl: returns +inf
@@ -71,229 +73,208 @@
 //
 // Registers used
 //==============================================================
-// general registers used: 
-// ar.pfs r32 
-// r33 -> r37
-// r38 -> r41 used as parameters to error path
+// general registers used:
+// r26 -> r38
+// r35 -> r38 used as parameters to error path
 //
-// predicate registers used: 
+// predicate registers used:
 // p6, p7, p8
-//
-// floating-point registers used: 
+// floating-point registers used:
 // f9, f10, f11
 // f8, input
 
-#include "libm_support.h"
+rExpBias            = r26
+rExpMask            = r27
+rSignexp_x          = r28
+rExp_x              = r29
+rTrueExp_x          = r30
+rExp_2to64          = r31
 
 GR_SAVE_PFS         = r32
-GR_SAVE_B0          = r34
-GR_SAVE_GP          = r35
-GR_Parameter_X      = r38
-GR_Parameter_Y      = r39
-GR_Parameter_RESULT = r40
-GR_Parameter_TAG    = r41
+GR_SAVE_B0          = r33
+GR_SAVE_GP          = r34
 
-FR_X                = f8
-FR_Y                = f0
-FR_RESULT           = f10
+GR_Parameter_X      = r35
+GR_Parameter_Y      = r36
+GR_Parameter_RESULT = r37
+GR_Parameter_TAG    = r38
 
-.align 32
-.global logbl#
+fExp_in_signif      = f9
+fNorm_x             = f10
+fFloat_Exp          = f10
+f2to64              = f11
 
 .section .text
-.proc  logbl#
-.align 32
-
+GLOBAL_LIBM_ENTRY(logbl)
 
-logbl: 
-
-// qnan snan inf norm     unorm 0 -+
-// 0    0    0   0        1     0 11
-// 0                      b
-{ .mfi
-      alloc          r32=ar.pfs,1,5,4,0
-(p0)  fclass.m.unc  p8,p0 = f8, 0x0b
-      nop.i 999
-}
 // X NORMAL
-// r37 = exp(f8) - - 0xffff
-// sig(f8) = r37
+// TrueExp_x = exp(f8) - 0xffff
+// sig = TrueExp_x
 // f8 = convert_to_fp (sig))
 { .mfi
-(p0)  getf.exp      r35 = f8
-(p0)  fnorm         f10=f8
-      nop.i 999 ;;
+      getf.exp        rSignexp_x = f8
+      fclass.m        p8,p0 = f8, 0x0b   // Test for x unorm
+      mov             rExpBias = 0xffff  // Exponent bias
 }
-
-// qnan snan inf norm     unorm 0 -+
-// 1    1    1   0        0     0 11
-// e                      3
-{ .mmf
-(p0)  mov      r33 = 0xffff
-(p0)  mov      r34 = 0x1ffff
-(p0)  fclass.m.unc  p6,p0 = f8, 0xe3 ;;
+{ .mfi
+      nop.m           0
+      fnorm.s1        fNorm_x = f8
+      mov             rExpMask = 0x1ffff // Exponent mask
 }
+;;
 
+// Form signexp of 2^64 in case need to scale denormal
 { .mfb
-(p0)  and           r36 = r35, r34
-(p0)  fclass.m.unc  p7,p0 = f8, 0x07
-(p8)  br.cond.spnt  L(LOGB_DENORM) ;;
+      mov             rExp_2to64 = 0x1003f
+      fclass.m        p6,p0 = f8, 0x1e3  // Test x natval, nan, inf
+(p8)  br.cond.spnt    LOGB_DENORM        // Branch if x unorm
 }
+;;
 
-{ .mib
-(p0)  sub           r37 = r36, r33
-      nop.i 999
-(p6)  br.cond.spnt  L(LOGB_NAN_INF) ;;
+LOGB_COMMON:
+// Return here from LOGB_DENORM
+{ .mfi
+      and             rExp_x = rSignexp_x, rExpMask // Get biased exponent
+      fclass.m        p7,p0 = f8, 0x07   // Test x zero
+      nop.i           0
 }
+;;
+
+// X NAN or INFINITY, return f8 * f8
+{ .mfb
+      sub             rTrueExp_x = rExp_x, rExpBias // Get true exponent
+(p6)  fma.s0          f8= f8,f8,f0       // Result if x natval, nan, inf
+(p6)  br.ret.spnt     b0                 // Exit if x natval, nan, inf
+}
+;;
 
 { .mib
-(p0)  setf.sig      f9  = r37
+      setf.sig        fExp_in_signif = rTrueExp_x // Exponent as integer in fp
       nop.i 999
-(p7)  br.cond.spnt  L(LOGB_ZERO) ;;
-}
-{ .mfi
-      nop.m 999
-(p0)  fcvt.xf       f10 = f9
-      nop.i 999 ;;
+(p7)  br.cond.spnt    LOGB_ZERO
 }
+;;
 
+// Result can be represented in less than 24 bits, so no precision completer
+// is needed.
 { .mfb
-      nop.m 999
-(p0)  fnorm       f8 = f10
-(p0)  br.ret.sptk    b0 ;;
+      nop.m           0
+      fcvt.xf         f8 = fExp_in_signif
+      br.ret.sptk     b0                 // Exit main path, 0 < |x| < inf
 }
+;;
 
-L(LOGB_DENORM):
-// Form signexp of 2^64 in case need to scale denormal
+LOGB_DENORM:
+// Form 2^64 in case need to scale denormal
 // Check to see if double-extended denormal
 { .mfi
-(p0)  mov r38 = 0x1003f
-(p0)  fclass.m.unc  p8,p0 = f10, 0x0b
-      nop.i 999 ;;
+      setf.exp        f2to64 = rExp_2to64
+      fclass.m        p8,p0 = fNorm_x, 0x0b
+      nop.i           0
 }
+;;
 
-// Form 2^64 in case need to scale denormal
 { .mfi
-(p0)  setf.exp f11 = r38
-      nop.f 999
-      nop.i 999 ;;
+      nop.m           0
+      fcmp.eq.s0      p7,p0 = f8, f0           // Dummy op to set denormal flag
+      nop.i           0
 }
+;;
 
 // If double-extended denormal add 64 to exponent bias for scaling
 // If double-extended denormal form x * 2^64 which is normal
 { .mfi
-(p8)  add r33 = 64, r33
-(p8)  fmpy f10 = f10, f11    
-      nop.i 999 ;;
+(p8)  add             rExpBias = 64, rExpBias
+(p8)  fmpy.s1         fNorm_x = fNorm_x, f2to64
+      nop.i           0
 }
+;;
 
 // Logic is the same as normal path but use normalized input
-{ .mmi
-(p0)  getf.exp      r35 = f10 ;;
-      nop.m 999
-      nop.i 999 ;;
-}
-
-{ .mmi
-(p0)  and           r36 = r35, r34 ;;
-(p0)  sub           r37 = r36, r33
-      nop.i 999 ;;
-}
-
-{ .mmi
-(p0)  setf.sig      f9  = r37
-      nop.m 999
-      nop.i 999 ;;
+{ .mib
+      getf.exp        rSignexp_x = fNorm_x
+      nop.i           0
+      br.cond.sptk    LOGB_COMMON              // Return to main path
 }
+;;
 
-{ .mfi
-      nop.m 999
-(p0)  fcvt.xf       f10 = f9
-      nop.i 999 ;;
-}
+LOGB_ZERO:
+// Here if x zero
+// f10  = -|f8|
+// f9  = 1.0/f10 = -1.0/|f8| = -inf
 
-{ .mfb
-      nop.m 999
-(p0)  fnorm       f8 = f10
-(p0)  br.ret.sptk    b0 ;;
+{ .mmf
+      alloc           r32=ar.pfs,1,2,4,0
+      mov             GR_Parameter_TAG = 150  // Error code
+      fmerge.ns       f10 = f0,f8
 }
+;;
 
-L(LOGB_NAN_INF): 
-
-// X NAN or INFINITY, return f8 * f8
 { .mfb
-      nop.m 999
-(p0)  fma        f8= f8,f8,f0
-(p0)  br.ret.sptk   b0 ;;
+      nop.m           0
+      frcpa.s0        f9,p6 = f1,f10          // Produce -inf, Z flag
+      br.cond.sptk    __libm_error_region     // Call error support
 }
+;;
 
-L(LOGB_ZERO): 
-{.mfi
-      nop.m 0
-(p0)  frcpa.s0       f10,p6 = f1,f0
-      nop.i 0
-};;
-{.mfi
-      mov            GR_Parameter_TAG = 150
-(p0)  fms.s1         f10 = f0,f0,f10
-      nop.i 0
-};;
-// X ZERO
-// return -1.0/fabs(f8)=-inf, set divide-by-zero flag, call error support
-.endp logbl
-ASM_SIZE_DIRECTIVE(logbl)
+GLOBAL_LIBM_END(logbl)
 
-.proc __libm_error_region
-__libm_error_region:
+LOCAL_LIBM_ENTRY(__libm_error_region)
 .prologue
+
 { .mfi
-        add   GR_Parameter_Y=-32,sp             // Parameter 2 value
+        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
+        mov  GR_SAVE_PFS=ar.pfs               // Save ar.pfs
 }
 { .mfi
 .fframe 64
-        add sp=-64,sp                           // Create new stack
+        add sp=-64,sp                         // Create new stack
         nop.f 0
-        mov GR_SAVE_GP=gp                       // Save gp
+        mov GR_SAVE_GP=gp                     // Save gp
 };;
+
 { .mmi
-        stfe [GR_Parameter_Y] = FR_Y,16         // Save Parameter 2 on stack
-        add GR_Parameter_X = 16,sp              // Parameter 1 address
+        stfe [GR_Parameter_Y] = f0,16         // 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
+        mov GR_SAVE_B0=b0                     // Save b0
 };;
+
 .body
 { .mib
-        stfe [GR_Parameter_X] = FR_X            // Store Parameter 1 on stack
-        add   GR_Parameter_RESULT = 0,GR_Parameter_Y
-        nop.b 0                                 // Parameter 3 address
+        stfe [GR_Parameter_X] = f8            // STORE Parameter 1 on stack
+        add   GR_Parameter_RESULT = 0,GR_Parameter_Y    // Parameter 3 address
+        nop.b 0
 }
 { .mib
-        stfe [GR_Parameter_Y] = FR_RESULT      // Store Parameter 3 on stack
+        stfe [GR_Parameter_Y] = f9            // Store Parameter 3 on stack
         add   GR_Parameter_Y = -16,GR_Parameter_Y
-        br.call.sptk b0=__libm_error_support#  // Call error handling function
+        br.call.sptk b0=__libm_error_support# // Call error handling function
 };;
+
 { .mmi
-        nop.m 0
-        nop.m 0
         add   GR_Parameter_RESULT = 48,sp
+        nop.m 0
+        nop.i 0
 };;
+
 { .mmi
         ldfe  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
+        br.ret.sptk   b0
 };;
 
-.endp __libm_error_region
-ASM_SIZE_DIRECTIVE(__libm_error_region)
+LOCAL_LIBM_END(__libm_error_region)
+
 
 .type   __libm_error_support#,@function
 .global __libm_error_support#