Re: [Patch] (revised patch) / 0 should send SIGFPE not SIGTRAP

[David Daney <ddaney at avtrex dot com>]

David Daney wrote:

> How about the attached (lightly tested) patch?
I will quit sending patches after this one.  It is equivalent to the 
previous version, except it uses the symbolic names of the break codes 
instead of the numeric values.

David Daney.


*** ../linux-avtrex/linux/arch/mips/kernel/traps.c	2004-02-26 11:14:09.000000000 -0800
--- arch/mips/kernel/traps.c	2004-06-11 14:04:52.000000000 -0700
***************
*** 38,43 ****
--- 38,44 ----
  #include <asm/traps.h>
  #include <asm/uaccess.h>
  #include <asm/mmu_context.h>
+ #include <asm/break.h>
  
  extern asmlinkage void handle_mod(void);
  extern asmlinkage void handle_tlbl(void);
***************
*** 597,615 ****
  	 * There is the ancient bug in the MIPS assemblers that the break
  	 * code starts left to bit 16 instead to bit 6 in the opcode.
  	 * Gas is bug-compatible ...
! 	 */
! 	bcode = ((opcode >> 16) & ((1 << 20) - 1));
! 
! 	/*
  	 * (A short test says that IRIX 5.3 sends SIGTRAP for all break
  	 * insns, even for break codes that indicate arithmetic failures.
  	 * Weird ...)
  	 * But should we continue the brokenness???  --macro
  	 */
  	switch (bcode) {
! 	case 6:
! 	case 7:
! 		if (bcode == 7)
  			info.si_code = FPE_INTDIV;
  		else
  			info.si_code = FPE_INTOVF;
--- 598,622 ----
  	 * There is the ancient bug in the MIPS assemblers that the break
  	 * code starts left to bit 16 instead to bit 6 in the opcode.
  	 * Gas is bug-compatible ...
! 	 *
  	 * (A short test says that IRIX 5.3 sends SIGTRAP for all break
  	 * insns, even for break codes that indicate arithmetic failures.
  	 * Weird ...)
  	 * But should we continue the brokenness???  --macro
+          *
+          * It seems some assemblers (binutils-2.15 for example) assemble
+          * break correctly.  So we check for the break code in either
+          * position.
+          *
  	 */
+ 
+ 	bcode = ((opcode >> 6) & ((1 << 20) - 1));
  	switch (bcode) {
! 	case BRK_OVERFLOW:
! 	case BRK_DIVZERO:
!         case BRK_OVERFLOW << 10:
!         case BRK_DIVZERO << 10:
! 		if (bcode == BRK_DIVZERO || bcode == (BRK_DIVZERO << 10))
  			info.si_code = FPE_INTDIV;
  		else
  			info.si_code = FPE_INTOVF;
***************
*** 633,639 ****
  
  	/* Immediate versions don't provide a code.  */
  	if (!(opcode & OPCODE))
! 		tcode = ((opcode >> 6) & ((1 << 20) - 1));
  
  	/*
  	 * (A short test says that IRIX 5.3 sends SIGTRAP for all trap
--- 640,646 ----
  
  	/* Immediate versions don't provide a code.  */
  	if (!(opcode & OPCODE))
! 		tcode = ((opcode >> 6) & ((1 << 10) - 1));
  
  	/*
  	 * (A short test says that IRIX 5.3 sends SIGTRAP for all trap