search for: newinstr

...0 files changed, 141 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/alternative-asm.h b/arch/x86/include/asm/alternative-asm.h index 60073947350d..0ced2e3d0a30 100644 --- a/arch/x86/include/asm/alternative-asm.h +++ b/arch/x86/include/asm/alternative-asm.h @@ -39,14 +39,14 @@ * @newinstr. ".skip" directive takes care of proper instruction padding * in case @newinstr is longer than @oldinstr. */ -#define ALTERNATIVE(oldinstr, newinstr, feature) \ +#define __ALTERNATIVE(section, oldinstr, newinstr, feature) \ 140:; \ oldinstr; \ 141:; \ .s...

...;0" (x) + :"memory"); + break; + } + return x; +} + +/* + * Alternative instructions for different CPU types or capabilities. + * + * This allows to use optimized instructions even on generic binary + * kernels. + * + * length of oldinstr must be longer or equal the length of newinstr + * It can be padded with nops as needed. + * + * For non barrier like inlines please define new variants + * without volatile and memory clobber. + */ +#define alternative(oldinstr, newinstr, feature) \ + asm volatile ("661:\n\t" oldinstr "\n662:\n" \ + ".s...

...;0" (x) + :"memory"); + break; + } + return x; +} + +/* + * Alternative instructions for different CPU types or capabilities. + * + * This allows to use optimized instructions even on generic binary + * kernels. + * + * length of oldinstr must be longer or equal the length of newinstr + * It can be padded with nops as needed. + * + * For non barrier like inlines please define new variants + * without volatile and memory clobber. + */ +#define alternative(oldinstr, newinstr, feature) \ + asm volatile ("661:\n\t" oldinstr "\n662:\n" \ + ".s...

...EATURE_SEP) #endif /* Enter using int $0x80 */ diff --git a/arch/x86/include/asm/alternative-asm.h b/arch/x86/include/asm/alternative-asm.h index e7636bac7372..60073947350d 100644 --- a/arch/x86/include/asm/alternative-asm.h +++ b/arch/x86/include/asm/alternative-asm.h @@ -39,23 +39,21 @@ * @newinstr. ".skip" directive takes care of proper instruction padding * in case @newinstr is longer than @oldinstr. */ -.macro ALTERNATIVE oldinstr, newinstr, feature -140: - \oldinstr -141: - .skip -(((144f-143f)-(141b-140b)) > 0) * ((144f-143f)-(141b-140b)),0x90 -142: - - .pushsection .alt...

I read the tutorial document, but I didn't understand the it and Ops fields of instruction class well. Can any one give me an example? Instruction *newInstr = new Instruction(Type *ty, unsigned it, Use *Ops, unsigned NumOps, Instruction *InsertBefore); For example, I have an *instruction *pInst *without no the type of operation in advance. If I want to create a new instruction which is similar to the *pInst. *How can I do it? Any help will be appreci...

This changes the pv ops code generation to more closely match reality. For example, instead of: callq *0xffffffff81e3a400 (pv_irq_ops.save_fl) vmlinux will now show: pushfq pop %rax nop nop nop nop nop which is what the runtime version of the code will show in most cases. This idea was suggested by Andy Lutomirski. The benefits are: - For the most common runtime cases

This changes the pv ops code generation to more closely match reality. For example, instead of: callq *0xffffffff81e3a400 (pv_irq_ops.save_fl) vmlinux will now show: pushfq pop %rax nop nop nop nop nop which is what the runtime version of the code will show in most cases. This idea was suggested by Andy Lutomirski. The benefits are: - For the most common runtime cases

Hi all, This is version three of the patches I previously posted here: v1: https://lore.kernel.org/lkml/20191108170120.22331-1-will at kernel.org/ v2: https://lore.kernel.org/r/20200630173734.14057-1-will at kernel.org Changes since v2 include: * Actually add the barrier in READ_ONCE() for Alpha! * Implement Alpha's smp_load_acquire() using __READ_ONCE(), rather than the other

Hi everyone, This is the long-awaited version two of the patches I previously posted in November last year: https://lore.kernel.org/lkml/20191108170120.22331-1-will at kernel.org/ I ended up parking the series while the READ_ONCE() implementation was being overhauled, but with that merged during the recent merge window and LTO patches being posted again [1], it was time for a refresh. The

Hi everyone, This is the long-awaited version two of the patches I previously posted in November last year: https://lore.kernel.org/lkml/20191108170120.22331-1-will at kernel.org/ I ended up parking the series while the READ_ONCE() implementation was being overhauled, but with that merged during the recent merge window and LTO patches being posted again [1], it was time for a refresh. The

...E_CONSTRAINT] "i" (PARAVIRT_PATCH(op)), \ + [PV_CALL_CONSTRAINT] "i" (&(op)), \ + [PV_CLBR_CONSTRAINT] "i" (clobber) + +#define PV_SITE(insn_string) \ + _PV_SITE(insn_string, PV_TYPE_CONSTRAINT_STR, PV_CLBR_CONSTRAINT_STR) + +#define PV_ALT_SITE(oldinstr, newinstr) \ + _PV_ALT_SITE(oldinstr, newinstr, PV_TYPE_CONSTRAINT_STR, \ + PV_CLBR_CONSTRAINT_STR) /* * These macros are intended to wrap calls through one of the paravirt @@ -525,25 +531,24 @@ int paravirt_disable_iospace(void); #define ____PVOP_CALL(rettype, op, clbr, call_clbr, extra_cl...

On Wed, Oct 10, 2018 at 01:54:33PM -0500, Segher Boessenkool wrote: > It would be great to hear from kernel people if it works adequately for > what you guys want it for :-) Sure, ping me when you have the final version and I'll try to build gcc with it and do some size comparisons. Thx. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the

On Wed, Oct 10, 2018 at 01:54:33PM -0500, Segher Boessenkool wrote: > It would be great to hear from kernel people if it works adequately for > what you guys want it for :-) Sure, ping me when you have the final version and I'll try to build gcc with it and do some size comparisons. Thx. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the

Ralf Karrenberg wrote: > Hello everyone, > > is there any way to replace an instruction inside LLVM that is more > elegant than creating a new one, replacing uses and deleting the old one > if I only want to modify the type? It is generally not a big deal, but > the issue gets really messy if I am in the middle of iterating over uses > and start deleting some of them... >

...blob/master/include/llvm/IR/Instruction.h#L395 > > Jon > > On 4/16/15 6:38 PM, zhi chen wrote: > >> I read the tutorial document, but I didn't understand the it and Ops >> fields of instruction class well. Can any one give me an example? >> >> Instruction *newInstr = new Instruction(Type *ty, unsigned it, Use *Ops, >> unsigned NumOps, Instruction *InsertBefore); >> >> For example, I have an *instruction *pInst *without no the type of >> operation in advance. If I want to create a new instruction which is >> similar to the *pInst....

Hello everyone, is there any way to replace an instruction inside LLVM that is more elegant than creating a new one, replacing uses and deleting the old one if I only want to modify the type? It is generally not a big deal, but the issue gets really messy if I am in the middle of iterating over uses and start deleting some of them... I hope I could describe my problem well enough ;) Regards,