diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc32/fpu/s_lround.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc32/fpu/s_lround.S | 52 |
1 files changed, 26 insertions, 26 deletions
diff --git a/sysdeps/powerpc/powerpc32/fpu/s_lround.S b/sysdeps/powerpc/powerpc32/fpu/s_lround.S index 9c534ec2be..ebaccccd9b 100644 --- a/sysdeps/powerpc/powerpc32/fpu/s_lround.S +++ b/sysdeps/powerpc/powerpc32/fpu/s_lround.S @@ -1,5 +1,5 @@ /* lround function. PowerPC32 version. - Copyright (C) 2004, 2006 Free Software Foundation, Inc. + Copyright (C) 2004, 2006, 2007 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -20,13 +20,10 @@ #include <sysdep.h> #include <math_ldbl_opt.h> - .section .rodata.cst8,"aM",@progbits,8 + .section .rodata.cst4,"aM",@progbits,4 .align 2 -.LC0: /* 0.0 */ - .long 0x00000000 -.LC1: /* 0.5 */ +.LC0: /* 0.5 */ .long 0x3f000000 - .section ".text" /* long [r3] lround (float x [fp1]) @@ -37,7 +34,10 @@ tie, choose the one that is even (least significant bit o).". So we can't use the PowerPC "round to Nearest" mode. Instead we set "round toward Zero" mode and round by adding +-0.5 before rounding - to the integer value. */ + to the integer value. It is necessary to detect when x is + (+-)0x1.fffffffffffffp-2 because adding +-0.5 in this case will + cause an erroneous shift, carry and round. We simply return 0 if + 0.5 > x > -0.5. */ ENTRY (__lround) stwu r1,-16(r1) @@ -49,40 +49,40 @@ ENTRY (__lround) bcl 20,31,1f 1: mflr r9 addis r9,r9,.LC0-1b@ha - addi r9,r9,.LC0-1b@l + lfs fp10,.LC0-1b@l(r9) # else bl _GLOBAL_OFFSET_TABLE_@local-4 mflr r10 lwz r9,.LC0@got(10) + lfs fp10,0(r9) # endif mtlr r11 cfi_same_value (lr) - lfs fp12,0(r9) #else lis r9,.LC0@ha - lfs fp12,.LC0@l(r9) -#endif -#ifdef SHARED - lfs fp10,.LC1-.LC0(r9) -#else - lis r9,.LC1@ha - lfs fp10,.LC1@l(r9) + lfs fp10,.LC0@l(r9) #endif - fcmpu cr6,fp1,fp12 /* if (x > 0.0) */ - ble- cr6,.L4 - fadd fp1,fp1,fp10 /* x+= 0.5; */ -.L9: - fctiwz fp2,fp1 /* Convert To Integer DW lround toward 0. */ - stfd fp2,8(r1) + fabs fp2, fp1 /* Get the absolute value of x. */ + fsub fp12,fp10,fp10 /* Compute 0.0. */ + fcmpu cr6, fp2, fp10 /* if |x| < 0.5 */ + fcmpu cr3, fp1, fp12 /* x is negative? x < 0.0 */ + blt- cr6,.Lretzero + fadd fp3,fp2,fp10 /* |x|+=0.5 bias to prepare to round. */ + bge cr3,.Lconvert /* x is positive so don't negate x. */ + fnabs fp3,fp3 /* -(|x|+=0.5) */ +.Lconvert: + fctiwz fp4,fp3 /* Convert to Integer word lround toward 0. */ + stfd fp4,8(r1) nop /* Ensure the following load is in a different dispatch */ nop /* group to avoid pipe stall on POWER4&5. */ nop - lwz r3,12(r1) + lwz r3,12(r1) /* Load return as integer. */ +.Lout: addi r1,r1,16 blr -.L4: - fsub fp1,fp1,fp10 /* x-= 0.5; */ - b .L9 +.Lretzero: /* when 0.5 > x > -0.5 */ + li r3,0 /* return 0. */ + b .Lout END (__lround) weak_alias (__lround, lround) |