Messages in this thread | | | Date | Mon, 24 Nov 2008 19:04:40 +0000 (GMT) | From | "Maciej W. Rozycki" <> | Subject | Re: [PATCH] MIPS: Make BUG() __noreturn. |
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On Fri, 21 Nov 2008, Ralf Baechle wrote:
> MIPS ISA newer than MIPS I also have conditional break codes allowing > something like this: > > #define BUG_ON(condition) \ > do { \ > __asm__ __volatile__("tne $0, %0, %1" \ > : : "r" (condition), "i" (BRK_BUG)); \ > } while (0) > > that is test of condition and the trap as a single instruction. Note there > are break and trap instructions on MIPS and they are basically doing the > same job ...
GCC is actually smart enough to combine sequences like:
if (something) __builtin_trap();
into appropriate conditional trap instructions on MIPS. As noted by David trap codes other than the default cannot be emitted this way though.
Maciej
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