aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/arch/x86/math-emu/poly_l2.c
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2008-01-30 13:30:11 +0100
committerIngo Molnar <mingo@elte.hu>2008-01-30 13:30:11 +0100
commit3d0d14f983b55a570b976976284df4c434af3223 (patch)
tree864f11c0ce5ee1e15acdd196018b79d0d0e2685d /arch/x86/math-emu/poly_l2.c
parentx86: mach-voyager, lindent (diff)
downloadwireguard-linux-3d0d14f983b55a570b976976284df4c434af3223.tar.xz
wireguard-linux-3d0d14f983b55a570b976976284df4c434af3223.zip
x86: lindent arch/i386/math-emu
lindent these files: errors lines of code errors/KLOC arch/x86/math-emu/ 2236 9424 237.2 arch/x86/math-emu/ 128 8706 14.7 no other changes. No code changed: text data bss dec hex filename 5589802 612739 3833856 10036397 9924ad vmlinux.before 5589802 612739 3833856 10036397 9924ad vmlinux.after the intent of this patch is to ease the automated tracking of kernel code quality - it's just much easier for us to maintain it if every file in arch/x86 is supposed to be clean. NOTE: it is a known problem of lindent that it causes some style damage of its own, but it's a safe tool (well, except for the gcc array range initializers extension), so we did the bulk of the changes via lindent, and did the manual fixups in a followup patch. the resulting math-emu code has been tested by Thomas Gleixner on a real 386 DX CPU as well, and it works fine. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/math-emu/poly_l2.c')
-rw-r--r--arch/x86/math-emu/poly_l2.c378
1 files changed, 175 insertions, 203 deletions
diff --git a/arch/x86/math-emu/poly_l2.c b/arch/x86/math-emu/poly_l2.c
index dd00e1d5b074..c0102ae87511 100644
--- a/arch/x86/math-emu/poly_l2.c
+++ b/arch/x86/math-emu/poly_l2.c
@@ -10,7 +10,6 @@
| |
+---------------------------------------------------------------------------*/
-
#include "exception.h"
#include "reg_constant.h"
#include "fpu_emu.h"
@@ -18,255 +17,228 @@
#include "control_w.h"
#include "poly.h"
-
static void log2_kernel(FPU_REG const *arg, u_char argsign,
- Xsig *accum_result, long int *expon);
-
+ Xsig * accum_result, long int *expon);
/*--- poly_l2() -------------------------------------------------------------+
| Base 2 logarithm by a polynomial approximation. |
+---------------------------------------------------------------------------*/
-void poly_l2(FPU_REG *st0_ptr, FPU_REG *st1_ptr, u_char st1_sign)
+void poly_l2(FPU_REG * st0_ptr, FPU_REG * st1_ptr, u_char st1_sign)
{
- long int exponent, expon, expon_expon;
- Xsig accumulator, expon_accum, yaccum;
- u_char sign, argsign;
- FPU_REG x;
- int tag;
-
- exponent = exponent16(st0_ptr);
-
- /* From st0_ptr, make a number > sqrt(2)/2 and < sqrt(2) */
- if ( st0_ptr->sigh > (unsigned)0xb504f334 )
- {
- /* Treat as sqrt(2)/2 < st0_ptr < 1 */
- significand(&x) = - significand(st0_ptr);
- setexponent16(&x, -1);
- exponent++;
- argsign = SIGN_NEG;
- }
- else
- {
- /* Treat as 1 <= st0_ptr < sqrt(2) */
- x.sigh = st0_ptr->sigh - 0x80000000;
- x.sigl = st0_ptr->sigl;
- setexponent16(&x, 0);
- argsign = SIGN_POS;
- }
- tag = FPU_normalize_nuo(&x);
-
- if ( tag == TAG_Zero )
- {
- expon = 0;
- accumulator.msw = accumulator.midw = accumulator.lsw = 0;
- }
- else
- {
- log2_kernel(&x, argsign, &accumulator, &expon);
- }
-
- if ( exponent < 0 )
- {
- sign = SIGN_NEG;
- exponent = -exponent;
- }
- else
- sign = SIGN_POS;
- expon_accum.msw = exponent; expon_accum.midw = expon_accum.lsw = 0;
- if ( exponent )
- {
- expon_expon = 31 + norm_Xsig(&expon_accum);
- shr_Xsig(&accumulator, expon_expon - expon);
-
- if ( sign ^ argsign )
- negate_Xsig(&accumulator);
- add_Xsig_Xsig(&accumulator, &expon_accum);
- }
- else
- {
- expon_expon = expon;
- sign = argsign;
- }
-
- yaccum.lsw = 0; XSIG_LL(yaccum) = significand(st1_ptr);
- mul_Xsig_Xsig(&accumulator, &yaccum);
-
- expon_expon += round_Xsig(&accumulator);
-
- if ( accumulator.msw == 0 )
- {
- FPU_copy_to_reg1(&CONST_Z, TAG_Zero);
- return;
- }
-
- significand(st1_ptr) = XSIG_LL(accumulator);
- setexponent16(st1_ptr, expon_expon + exponent16(st1_ptr) + 1);
-
- tag = FPU_round(st1_ptr, 1, 0, FULL_PRECISION, sign ^ st1_sign);
- FPU_settagi(1, tag);
-
- set_precision_flag_up(); /* 80486 appears to always do this */
-
- return;
+ long int exponent, expon, expon_expon;
+ Xsig accumulator, expon_accum, yaccum;
+ u_char sign, argsign;
+ FPU_REG x;
+ int tag;
+
+ exponent = exponent16(st0_ptr);
+
+ /* From st0_ptr, make a number > sqrt(2)/2 and < sqrt(2) */
+ if (st0_ptr->sigh > (unsigned)0xb504f334) {
+ /* Treat as sqrt(2)/2 < st0_ptr < 1 */
+ significand(&x) = -significand(st0_ptr);
+ setexponent16(&x, -1);
+ exponent++;
+ argsign = SIGN_NEG;
+ } else {
+ /* Treat as 1 <= st0_ptr < sqrt(2) */
+ x.sigh = st0_ptr->sigh - 0x80000000;
+ x.sigl = st0_ptr->sigl;
+ setexponent16(&x, 0);
+ argsign = SIGN_POS;
+ }
+ tag = FPU_normalize_nuo(&x);
-}
+ if (tag == TAG_Zero) {
+ expon = 0;
+ accumulator.msw = accumulator.midw = accumulator.lsw = 0;
+ } else {
+ log2_kernel(&x, argsign, &accumulator, &expon);
+ }
+
+ if (exponent < 0) {
+ sign = SIGN_NEG;
+ exponent = -exponent;
+ } else
+ sign = SIGN_POS;
+ expon_accum.msw = exponent;
+ expon_accum.midw = expon_accum.lsw = 0;
+ if (exponent) {
+ expon_expon = 31 + norm_Xsig(&expon_accum);
+ shr_Xsig(&accumulator, expon_expon - expon);
+
+ if (sign ^ argsign)
+ negate_Xsig(&accumulator);
+ add_Xsig_Xsig(&accumulator, &expon_accum);
+ } else {
+ expon_expon = expon;
+ sign = argsign;
+ }
+
+ yaccum.lsw = 0;
+ XSIG_LL(yaccum) = significand(st1_ptr);
+ mul_Xsig_Xsig(&accumulator, &yaccum);
+
+ expon_expon += round_Xsig(&accumulator);
+
+ if (accumulator.msw == 0) {
+ FPU_copy_to_reg1(&CONST_Z, TAG_Zero);
+ return;
+ }
+
+ significand(st1_ptr) = XSIG_LL(accumulator);
+ setexponent16(st1_ptr, expon_expon + exponent16(st1_ptr) + 1);
+ tag = FPU_round(st1_ptr, 1, 0, FULL_PRECISION, sign ^ st1_sign);
+ FPU_settagi(1, tag);
+
+ set_precision_flag_up(); /* 80486 appears to always do this */
+
+ return;
+
+}
/*--- poly_l2p1() -----------------------------------------------------------+
| Base 2 logarithm by a polynomial approximation. |
| log2(x+1) |
+---------------------------------------------------------------------------*/
-int poly_l2p1(u_char sign0, u_char sign1,
- FPU_REG *st0_ptr, FPU_REG *st1_ptr, FPU_REG *dest)
+int poly_l2p1(u_char sign0, u_char sign1,
+ FPU_REG * st0_ptr, FPU_REG * st1_ptr, FPU_REG * dest)
{
- u_char tag;
- long int exponent;
- Xsig accumulator, yaccum;
+ u_char tag;
+ long int exponent;
+ Xsig accumulator, yaccum;
- if ( exponent16(st0_ptr) < 0 )
- {
- log2_kernel(st0_ptr, sign0, &accumulator, &exponent);
+ if (exponent16(st0_ptr) < 0) {
+ log2_kernel(st0_ptr, sign0, &accumulator, &exponent);
- yaccum.lsw = 0;
- XSIG_LL(yaccum) = significand(st1_ptr);
- mul_Xsig_Xsig(&accumulator, &yaccum);
+ yaccum.lsw = 0;
+ XSIG_LL(yaccum) = significand(st1_ptr);
+ mul_Xsig_Xsig(&accumulator, &yaccum);
- exponent += round_Xsig(&accumulator);
+ exponent += round_Xsig(&accumulator);
- exponent += exponent16(st1_ptr) + 1;
- if ( exponent < EXP_WAY_UNDER ) exponent = EXP_WAY_UNDER;
+ exponent += exponent16(st1_ptr) + 1;
+ if (exponent < EXP_WAY_UNDER)
+ exponent = EXP_WAY_UNDER;
- significand(dest) = XSIG_LL(accumulator);
- setexponent16(dest, exponent);
+ significand(dest) = XSIG_LL(accumulator);
+ setexponent16(dest, exponent);
- tag = FPU_round(dest, 1, 0, FULL_PRECISION, sign0 ^ sign1);
- FPU_settagi(1, tag);
+ tag = FPU_round(dest, 1, 0, FULL_PRECISION, sign0 ^ sign1);
+ FPU_settagi(1, tag);
- if ( tag == TAG_Valid )
- set_precision_flag_up(); /* 80486 appears to always do this */
- }
- else
- {
- /* The magnitude of st0_ptr is far too large. */
+ if (tag == TAG_Valid)
+ set_precision_flag_up(); /* 80486 appears to always do this */
+ } else {
+ /* The magnitude of st0_ptr is far too large. */
- if ( sign0 != SIGN_POS )
- {
- /* Trying to get the log of a negative number. */
-#ifdef PECULIAR_486 /* Stupid 80486 doesn't worry about log(negative). */
- changesign(st1_ptr);
+ if (sign0 != SIGN_POS) {
+ /* Trying to get the log of a negative number. */
+#ifdef PECULIAR_486 /* Stupid 80486 doesn't worry about log(negative). */
+ changesign(st1_ptr);
#else
- if ( arith_invalid(1) < 0 )
- return 1;
+ if (arith_invalid(1) < 0)
+ return 1;
#endif /* PECULIAR_486 */
- }
+ }
- /* 80486 appears to do this */
- if ( sign0 == SIGN_NEG )
- set_precision_flag_down();
- else
- set_precision_flag_up();
- }
+ /* 80486 appears to do this */
+ if (sign0 == SIGN_NEG)
+ set_precision_flag_down();
+ else
+ set_precision_flag_up();
+ }
- if ( exponent(dest) <= EXP_UNDER )
- EXCEPTION(EX_Underflow);
+ if (exponent(dest) <= EXP_UNDER)
+ EXCEPTION(EX_Underflow);
- return 0;
+ return 0;
}
-
-
-
#undef HIPOWER
#define HIPOWER 10
-static const unsigned long long logterms[HIPOWER] =
-{
- 0x2a8eca5705fc2ef0LL,
- 0xf6384ee1d01febceLL,
- 0x093bb62877cdf642LL,
- 0x006985d8a9ec439bLL,
- 0x0005212c4f55a9c8LL,
- 0x00004326a16927f0LL,
- 0x0000038d1d80a0e7LL,
- 0x0000003141cc80c6LL,
- 0x00000002b1668c9fLL,
- 0x000000002c7a46aaLL
+static const unsigned long long logterms[HIPOWER] = {
+ 0x2a8eca5705fc2ef0LL,
+ 0xf6384ee1d01febceLL,
+ 0x093bb62877cdf642LL,
+ 0x006985d8a9ec439bLL,
+ 0x0005212c4f55a9c8LL,
+ 0x00004326a16927f0LL,
+ 0x0000038d1d80a0e7LL,
+ 0x0000003141cc80c6LL,
+ 0x00000002b1668c9fLL,
+ 0x000000002c7a46aaLL
};
static const unsigned long leadterm = 0xb8000000;
-
/*--- log2_kernel() ---------------------------------------------------------+
| Base 2 logarithm by a polynomial approximation. |
| log2(x+1) |
+---------------------------------------------------------------------------*/
-static void log2_kernel(FPU_REG const *arg, u_char argsign, Xsig *accum_result,
+static void log2_kernel(FPU_REG const *arg, u_char argsign, Xsig * accum_result,
long int *expon)
{
- long int exponent, adj;
- unsigned long long Xsq;
- Xsig accumulator, Numer, Denom, argSignif, arg_signif;
-
- exponent = exponent16(arg);
- Numer.lsw = Denom.lsw = 0;
- XSIG_LL(Numer) = XSIG_LL(Denom) = significand(arg);
- if ( argsign == SIGN_POS )
- {
- shr_Xsig(&Denom, 2 - (1 + exponent));
- Denom.msw |= 0x80000000;
- div_Xsig(&Numer, &Denom, &argSignif);
- }
- else
- {
- shr_Xsig(&Denom, 1 - (1 + exponent));
- negate_Xsig(&Denom);
- if ( Denom.msw & 0x80000000 )
- {
- div_Xsig(&Numer, &Denom, &argSignif);
- exponent ++;
- }
- else
- {
- /* Denom must be 1.0 */
- argSignif.lsw = Numer.lsw; argSignif.midw = Numer.midw;
- argSignif.msw = Numer.msw;
+ long int exponent, adj;
+ unsigned long long Xsq;
+ Xsig accumulator, Numer, Denom, argSignif, arg_signif;
+
+ exponent = exponent16(arg);
+ Numer.lsw = Denom.lsw = 0;
+ XSIG_LL(Numer) = XSIG_LL(Denom) = significand(arg);
+ if (argsign == SIGN_POS) {
+ shr_Xsig(&Denom, 2 - (1 + exponent));
+ Denom.msw |= 0x80000000;
+ div_Xsig(&Numer, &Denom, &argSignif);
+ } else {
+ shr_Xsig(&Denom, 1 - (1 + exponent));
+ negate_Xsig(&Denom);
+ if (Denom.msw & 0x80000000) {
+ div_Xsig(&Numer, &Denom, &argSignif);
+ exponent++;
+ } else {
+ /* Denom must be 1.0 */
+ argSignif.lsw = Numer.lsw;
+ argSignif.midw = Numer.midw;
+ argSignif.msw = Numer.msw;
+ }
}
- }
#ifndef PECULIAR_486
- /* Should check here that |local_arg| is within the valid range */
- if ( exponent >= -2 )
- {
- if ( (exponent > -2) ||
- (argSignif.msw > (unsigned)0xafb0ccc0) )
- {
- /* The argument is too large */
+ /* Should check here that |local_arg| is within the valid range */
+ if (exponent >= -2) {
+ if ((exponent > -2) || (argSignif.msw > (unsigned)0xafb0ccc0)) {
+ /* The argument is too large */
+ }
}
- }
#endif /* PECULIAR_486 */
- arg_signif.lsw = argSignif.lsw; XSIG_LL(arg_signif) = XSIG_LL(argSignif);
- adj = norm_Xsig(&argSignif);
- accumulator.lsw = argSignif.lsw; XSIG_LL(accumulator) = XSIG_LL(argSignif);
- mul_Xsig_Xsig(&accumulator, &accumulator);
- shr_Xsig(&accumulator, 2*(-1 - (1 + exponent + adj)));
- Xsq = XSIG_LL(accumulator);
- if ( accumulator.lsw & 0x80000000 )
- Xsq++;
-
- accumulator.msw = accumulator.midw = accumulator.lsw = 0;
- /* Do the basic fixed point polynomial evaluation */
- polynomial_Xsig(&accumulator, &Xsq, logterms, HIPOWER-1);
-
- mul_Xsig_Xsig(&accumulator, &argSignif);
- shr_Xsig(&accumulator, 6 - adj);
-
- mul32_Xsig(&arg_signif, leadterm);
- add_two_Xsig(&accumulator, &arg_signif, &exponent);
-
- *expon = exponent + 1;
- accum_result->lsw = accumulator.lsw;
- accum_result->midw = accumulator.midw;
- accum_result->msw = accumulator.msw;
+ arg_signif.lsw = argSignif.lsw;
+ XSIG_LL(arg_signif) = XSIG_LL(argSignif);
+ adj = norm_Xsig(&argSignif);
+ accumulator.lsw = argSignif.lsw;
+ XSIG_LL(accumulator) = XSIG_LL(argSignif);
+ mul_Xsig_Xsig(&accumulator, &accumulator);
+ shr_Xsig(&accumulator, 2 * (-1 - (1 + exponent + adj)));
+ Xsq = XSIG_LL(accumulator);
+ if (accumulator.lsw & 0x80000000)
+ Xsq++;
+
+ accumulator.msw = accumulator.midw = accumulator.lsw = 0;
+ /* Do the basic fixed point polynomial evaluation */
+ polynomial_Xsig(&accumulator, &Xsq, logterms, HIPOWER - 1);
+
+ mul_Xsig_Xsig(&accumulator, &argSignif);
+ shr_Xsig(&accumulator, 6 - adj);
+
+ mul32_Xsig(&arg_signif, leadterm);
+ add_two_Xsig(&accumulator, &arg_signif, &exponent);
+
+ *expon = exponent + 1;
+ accum_result->lsw = accumulator.lsw;
+ accum_result->midw = accumulator.midw;
+ accum_result->msw = accumulator.msw;
}