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/reg_u_add.S b/arch/i386/math-emu/reg_u_add.S
new file mode 100644
index 0000000..47c4c24
--- /dev/null
+++ b/arch/i386/math-emu/reg_u_add.S
@@ -0,0 +1,167 @@
+ .file "reg_u_add.S"
+/*---------------------------------------------------------------------------+
+ | reg_u_add.S |
+ | |
+ | Add two valid (TAG_Valid) FPU_REG numbers, of the same sign, and put the |
+ | result in a destination FPU_REG. |
+ | |
+ | Copyright (C) 1992,1993,1995,1997 |
+ | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia |
+ | E-mail billm@suburbia.net |
+ | |
+ | Call from C as: |
+ | int FPU_u_add(FPU_REG *arg1, FPU_REG *arg2, FPU_REG *answ, |
+ | int control_w) |
+ | Return value is the tag of the answer, or-ed with FPU_Exception if |
+ | one was raised, or -1 on internal error. |
+ | |
+ +---------------------------------------------------------------------------*/
+
+/*
+ | Kernel addition routine FPU_u_add(reg *arg1, reg *arg2, reg *answ).
+ | Takes two valid reg f.p. numbers (TAG_Valid), which are
+ | treated as unsigned numbers,
+ | and returns their sum as a TAG_Valid or TAG_Special f.p. number.
+ | The returned number is normalized.
+ | Basic checks are performed if PARANOID is defined.
+ */
+
+#include "exception.h"
+#include "fpu_emu.h"
+#include "control_w.h"
+
+.text
+ENTRY(FPU_u_add)
+ pushl %ebp
+ movl %esp,%ebp
+ pushl %esi
+ pushl %edi
+ pushl %ebx
+
+ movl PARAM1,%esi /* source 1 */
+ movl PARAM2,%edi /* source 2 */
+
+ movl PARAM6,%ecx
+ movl %ecx,%edx
+ subl PARAM7,%ecx /* exp1 - exp2 */
+ jge L_arg1_larger
+
+ /* num1 is smaller */
+ movl SIGL(%esi),%ebx
+ movl SIGH(%esi),%eax
+
+ movl %edi,%esi
+ movl PARAM7,%edx
+ negw %cx
+ jmp L_accum_loaded
+
+L_arg1_larger:
+ /* num1 has larger or equal exponent */
+ movl SIGL(%edi),%ebx
+ movl SIGH(%edi),%eax
+
+L_accum_loaded:
+ movl PARAM3,%edi /* destination */
+ movw %dx,EXP(%edi) /* Copy exponent to destination */
+
+ xorl %edx,%edx /* clear the extension */
+
+#ifdef PARANOID
+ testl $0x80000000,%eax
+ je L_bugged
+
+ testl $0x80000000,SIGH(%esi)
+ je L_bugged
+#endif /* PARANOID */
+
+/* The number to be shifted is in %eax:%ebx:%edx */
+ cmpw $32,%cx /* shrd only works for 0..31 bits */
+ jnc L_more_than_31
+
+/* less than 32 bits */
+ shrd %cl,%ebx,%edx
+ shrd %cl,%eax,%ebx
+ shr %cl,%eax
+ jmp L_shift_done
+
+L_more_than_31:
+ cmpw $64,%cx
+ jnc L_more_than_63
+
+ subb $32,%cl
+ jz L_exactly_32
+
+ shrd %cl,%eax,%edx
+ shr %cl,%eax
+ orl %ebx,%ebx
+ jz L_more_31_no_low /* none of the lowest bits is set */
+
+ orl $1,%edx /* record the fact in the extension */
+
+L_more_31_no_low:
+ movl %eax,%ebx
+ xorl %eax,%eax
+ jmp L_shift_done
+
+L_exactly_32:
+ movl %ebx,%edx
+ movl %eax,%ebx
+ xorl %eax,%eax
+ jmp L_shift_done
+
+L_more_than_63:
+ cmpw $65,%cx
+ jnc L_more_than_64
+
+ movl %eax,%edx
+ orl %ebx,%ebx
+ jz L_more_63_no_low
+
+ orl $1,%edx
+ jmp L_more_63_no_low
+
+L_more_than_64:
+ movl $1,%edx /* The shifted nr always at least one '1' */
+
+L_more_63_no_low:
+ xorl %ebx,%ebx
+ xorl %eax,%eax
+
+L_shift_done:
+ /* Now do the addition */
+ addl SIGL(%esi),%ebx
+ adcl SIGH(%esi),%eax
+ jnc L_round_the_result
+
+ /* Overflow, adjust the result */
+ rcrl $1,%eax
+ rcrl $1,%ebx
+ rcrl $1,%edx
+ jnc L_no_bit_lost
+
+ orl $1,%edx
+
+L_no_bit_lost:
+ incw EXP(%edi)
+
+L_round_the_result:
+ jmp fpu_reg_round /* Round the result */
+
+
+
+#ifdef PARANOID
+/* If we ever get here then we have problems! */
+L_bugged:
+ pushl EX_INTERNAL|0x201
+ call EXCEPTION
+ pop %ebx
+ movl $-1,%eax
+ jmp L_exit
+
+L_exit:
+ popl %ebx
+ popl %edi
+ popl %esi
+ leave
+ ret
+#endif /* PARANOID */