Commit b114b68a authored by Richard Henderson's avatar Richard Henderson
Browse files

target-alpha: Consider the superpage when threading and ending TBs 



This allows significantly more threading, and occasionally larger TBs,
when processing code for the kernel and PALcode.

Signed-off-by: default avatarRichard Henderson <rth@twiddle.net>
parent a9ead832

target-alpha/translate.c

+29 −8
Original line number Diff line number Diff line
@@ -379,13 +379,26 @@ static ExitStatus gen_store_conditional(DisasContext *ctx, int ra, int rb, 
#endif

}



static int use_goto_tb(DisasContext *ctx, uint64_t dest)

static bool in_superpage(DisasContext *ctx, int64_t addr)

{

    /* Check for the dest on the same page as the start of the TB.  We

       also want to suppress goto_tb in the case of single-steping and IO.  */

    return (((ctx->tb->pc ^ dest) & TARGET_PAGE_MASK) == 0

            && !ctx->singlestep_enabled

            && !(ctx->tb->cflags & CF_LAST_IO));

    return ((ctx->tb->flags & TB_FLAGS_USER_MODE) == 0

            && addr < 0

            && ((addr >> 41) & 3) == 2

            && addr >> TARGET_VIRT_ADDR_SPACE_BITS == addr >> 63);

}



static bool use_goto_tb(DisasContext *ctx, uint64_t dest)

{

    /* Suppress goto_tb in the case of single-steping and IO.  */

    if (ctx->singlestep_enabled || (ctx->tb->cflags & CF_LAST_IO)) {

        return false;

    }

    /* If the destination is in the superpage, the page perms can't change.  */

    if (in_superpage(ctx, dest)) {

        return true;

    }

    /* Check for the dest on the same page as the start of the TB.  */

    return ((ctx->tb->pc ^ dest) & TARGET_PAGE_MASK) == 0;

}



static ExitStatus gen_bdirect(DisasContext *ctx, int ra, int32_t disp)
@@ -3431,6 +3444,7 @@ static inline void gen_intermediate_code_internal(AlphaCPU *cpu, 
    CPUAlphaState *env = &cpu->env;

    DisasContext ctx, *ctxp = &ctx;

    target_ulong pc_start;

    target_ulong pc_mask;

    uint32_t insn;

    uint16_t *gen_opc_end;

    CPUBreakpoint *bp;
@@ -3460,8 +3474,15 @@ static inline void gen_intermediate_code_internal(AlphaCPU *cpu, 


    num_insns = 0;

    max_insns = tb->cflags & CF_COUNT_MASK;

    if (max_insns == 0)

    if (max_insns == 0) {

        max_insns = CF_COUNT_MASK;

    }



    if (in_superpage(&ctx, pc_start)) {

        pc_mask = (1ULL << 41) - 1;

    } else {

        pc_mask = ~TARGET_PAGE_MASK;

    }



    gen_tb_start();

    do {
@@ -3499,7 +3520,7 @@ static inline void gen_intermediate_code_internal(AlphaCPU *cpu, 
        /* If we reach a page boundary, are single stepping,

           or exhaust instruction count, stop generation.  */

        if (ret == NO_EXIT

            && ((ctx.pc & (TARGET_PAGE_SIZE - 1)) == 0

            && ((ctx.pc & pc_mask) == 0

                || tcg_ctx.gen_opc_ptr >= gen_opc_end

                || num_insns >= max_insns

                || singlestep