IA-32 compatibility patch: FP denormal handling

IA-32 compatibility patch: FP denormal handling

[Arun Sharma]

[-- Attachment #1: Type: text/plain, Size: 219 bytes --]


The following patch makes ia64 compatible with i386 with respect to siginfo.si_code on FP denormal operands. This is necessary for the correct emulation of many IA-32 apps.

Please apply to both 2.4 and 2.5.

	-Arun



[-- Attachment #2: fp-denormal.patch --]
[-- Type: text/plain, Size: 519 bytes --]

--- linux/arch/ia64/kernel/traps.c.orig	Fri Apr 20 19:08:01 2001
+++ linux/arch/ia64/kernel/traps.c	Thu Jul  5 13:36:53 2001
@@ -325,6 +325,10 @@
 			siginfo.si_addr = (void *) (regs->cr_iip + ia64_psr(regs)->ri);
 			if (isr & 0x11) {
 				siginfo.si_code = FPE_FLTINV;
+			} else if (isr & 0x22) {
+				/* denormal operand gets the same si_code as underflow 
+				* see arch/i386/kernel/traps.c:math_error()  */
+				siginfo.si_code = FPE_FLTUND;
 			} else if (isr & 0x44) {
 				siginfo.si_code = FPE_FLTDIV;
 			}

Re: IA-32 compatibility patch: FP denormal handling

[David Mosberger]

>>>>> On Wed, 20 Aug 2003 13:39:51 -0700, Arun Sharma <adsharma@unix-os.sc.intel.com> said:

  Arun> The following patch makes ia64 compatible with i386 with
  Arun> respect to siginfo.si_code on FP denormal operands. This is
  Arun> necessary for the correct emulation of many IA-32 apps.

  Arun> Please apply to both 2.4 and 2.5.

Looks good to me.  I applied it (apologies for the garbled bk changelog
entry...).

	--david

Re: IA-32 compatibility patch: FP denormal handling

[Bjorn Helgaas]

On Wednesday 20 August 2003 2:39 pm, Arun Sharma wrote:
> 
> The following patch makes ia64 compatible with i386 with respect to siginfo.si_code on FP denormal operands. This is necessary for the correct emulation of many IA-32 apps.
> 
> Please apply to both 2.4 and 2.5.

Applied for 2.4, thanks!