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: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2013-07-26 14:05:08 -10:00
parent a9ead83261
commit b114b68adf

View File

@ -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