[dpdk-dev] [PATCH v2 02/16] vhost: unify unroll pragma parameter

[Tiwei Bie]

On Fri, Sep 20, 2019 at 12:36:29AM +0800, Marvin Liu wrote:
> Add macro for unifying Clang/ICC/GCC unroll pragma format. Burst
> functions were contained of several small loops which optimized by
> compiler’s loop unrolling pragma.
> 
> Signed-off-by: Marvin Liu <yong.liu at intel.com>
> 
> diff --git a/lib/librte_vhost/Makefile b/lib/librte_vhost/Makefile
> index 8623e91c0..30839a001 100644
> --- a/lib/librte_vhost/Makefile
> +++ b/lib/librte_vhost/Makefile
> @@ -16,6 +16,24 @@ CFLAGS += -I vhost_user
>  CFLAGS += -fno-strict-aliasing
>  LDLIBS += -lpthread
>  
> +ifeq ($(RTE_TOOLCHAIN), gcc)
> +ifeq ($(shell test $(GCC_VERSION) -ge 83 && echo 1), 1)
> +CFLAGS += -DSUPPORT_GCC_UNROLL_PRAGMA
> +endif
> +endif
> +
> +ifeq ($(RTE_TOOLCHAIN), clang)
> +ifeq ($(shell test $(CLANG_MAJOR_VERSION)$(CLANG_MINOR_VERSION) -ge 37 && echo 1), 1)
> +CFLAGS += -DSUPPORT_CLANG_UNROLL_PRAGMA
> +endif
> +endif
> +
> +ifeq ($(RTE_TOOLCHAIN), icc)
> +ifeq ($(shell test $(ICC_MAJOR_VERSION) -ge 16 && echo 1), 1)
> +CFLAGS += -DSUPPORT_ICC_UNROLL_PRAGMA
> +endif
> +endif
> +
>  ifeq ($(CONFIG_RTE_LIBRTE_VHOST_NUMA),y)
>  LDLIBS += -lnuma
>  endif

You need to add meson support as well.

> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
> index 884befa85..5074226f0 100644
> --- a/lib/librte_vhost/vhost.h
> +++ b/lib/librte_vhost/vhost.h
> @@ -39,6 +39,24 @@
>  
>  #define VHOST_LOG_CACHE_NR 32
>  
> +#ifdef SUPPORT_GCC_UNROLL_PRAGMA
> +#define PRAGMA_PARAM "GCC unroll 4"

The name "PRAGMA_PARAM" is too generic.

> +#endif
> +
> +#ifdef SUPPORT_CLANG_UNROLL_PRAGMA
> +#define PRAGMA_PARAM "unroll 4"
> +#endif
> +
> +#ifdef SUPPORT_ICC_UNROLL_PRAGMA
> +#define PRAGMA_PARAM "unroll (4)"
> +#endif
> +
> +#ifdef PRAGMA_PARAM
> +#define UNROLL_PRAGMA(param) _Pragma(param)
> +#else
> +#define UNROLL_PRAGMA(param) do {} while(0);
> +#endif
> +
>  /**
>   * Structure contains buffer address, length and descriptor index
>   * from vring to do scatter RX.
> -- 
> 2.17.1
>