Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/i386/math-emu/polynom_Xsig.S b/arch/i386/math-emu/polynom_Xsig.S
new file mode 100644
index 0000000..17315c8
--- /dev/null
+++ b/arch/i386/math-emu/polynom_Xsig.S
@@ -0,0 +1,135 @@
+/*---------------------------------------------------------------------------+
+ | polynomial_Xsig.S |
+ | |
+ | Fixed point arithmetic polynomial evaluation. |
+ | |
+ | Copyright (C) 1992,1993,1994,1995 |
+ | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, |
+ | Australia. E-mail billm@jacobi.maths.monash.edu.au |
+ | |
+ | Call from C as: |
+ | void polynomial_Xsig(Xsig *accum, unsigned long long x, |
+ | unsigned long long terms[], int n) |
+ | |
+ | Computes: |
+ | terms[0] + (terms[1] + (terms[2] + ... + (terms[n-1]*x)*x)*x)*x) ... )*x |
+ | and adds the result to the 12 byte Xsig. |
+ | The terms[] are each 8 bytes, but all computation is performed to 12 byte |
+ | precision. |
+ | |
+ | This function must be used carefully: most overflow of intermediate |
+ | results is controlled, but overflow of the result is not. |
+ | |
+ +---------------------------------------------------------------------------*/
+ .file "polynomial_Xsig.S"
+
+#include "fpu_emu.h"
+
+
+#define TERM_SIZE $8
+#define SUM_MS -20(%ebp) /* sum ms long */
+#define SUM_MIDDLE -24(%ebp) /* sum middle long */
+#define SUM_LS -28(%ebp) /* sum ls long */
+#define ACCUM_MS -4(%ebp) /* accum ms long */
+#define ACCUM_MIDDLE -8(%ebp) /* accum middle long */
+#define ACCUM_LS -12(%ebp) /* accum ls long */
+#define OVERFLOWED -16(%ebp) /* addition overflow flag */
+
+.text
+ENTRY(polynomial_Xsig)
+ pushl %ebp
+ movl %esp,%ebp
+ subl $32,%esp
+ pushl %esi
+ pushl %edi
+ pushl %ebx
+
+ movl PARAM2,%esi /* x */
+ movl PARAM3,%edi /* terms */
+
+ movl TERM_SIZE,%eax
+ mull PARAM4 /* n */
+ addl %eax,%edi
+
+ movl 4(%edi),%edx /* terms[n] */
+ movl %edx,SUM_MS
+ movl (%edi),%edx /* terms[n] */
+ movl %edx,SUM_MIDDLE
+ xor %eax,%eax
+ movl %eax,SUM_LS
+ movb %al,OVERFLOWED
+
+ subl TERM_SIZE,%edi
+ decl PARAM4
+ js L_accum_done
+
+L_accum_loop:
+ xor %eax,%eax
+ movl %eax,ACCUM_MS
+ movl %eax,ACCUM_MIDDLE
+
+ movl SUM_MIDDLE,%eax
+ mull (%esi) /* x ls long */
+ movl %edx,ACCUM_LS
+
+ movl SUM_MIDDLE,%eax
+ mull 4(%esi) /* x ms long */
+ addl %eax,ACCUM_LS
+ adcl %edx,ACCUM_MIDDLE
+ adcl $0,ACCUM_MS
+
+ movl SUM_MS,%eax
+ mull (%esi) /* x ls long */
+ addl %eax,ACCUM_LS
+ adcl %edx,ACCUM_MIDDLE
+ adcl $0,ACCUM_MS
+
+ movl SUM_MS,%eax
+ mull 4(%esi) /* x ms long */
+ addl %eax,ACCUM_MIDDLE
+ adcl %edx,ACCUM_MS
+
+ testb $0xff,OVERFLOWED
+ jz L_no_overflow
+
+ movl (%esi),%eax
+ addl %eax,ACCUM_MIDDLE
+ movl 4(%esi),%eax
+ adcl %eax,ACCUM_MS /* This could overflow too */
+
+L_no_overflow:
+
+/*
+ * Now put the sum of next term and the accumulator
+ * into the sum register
+ */
+ movl ACCUM_LS,%eax
+ addl (%edi),%eax /* term ls long */
+ movl %eax,SUM_LS
+ movl ACCUM_MIDDLE,%eax
+ adcl (%edi),%eax /* term ls long */
+ movl %eax,SUM_MIDDLE
+ movl ACCUM_MS,%eax
+ adcl 4(%edi),%eax /* term ms long */
+ movl %eax,SUM_MS
+ sbbb %al,%al
+ movb %al,OVERFLOWED /* Used in the next iteration */
+
+ subl TERM_SIZE,%edi
+ decl PARAM4
+ jns L_accum_loop
+
+L_accum_done:
+ movl PARAM1,%edi /* accum */
+ movl SUM_LS,%eax
+ addl %eax,(%edi)
+ movl SUM_MIDDLE,%eax
+ adcl %eax,4(%edi)
+ movl SUM_MS,%eax
+ adcl %eax,8(%edi)
+
+ popl %ebx
+ popl %edi
+ popl %esi
+ leave
+ ret