tcg: Introduce goto_ptr opcode and tcg_gen_lookup_and_goto_ptr

Instead of exporting goto_ptr directly to TCG frontends, export
tcg_gen_lookup_and_goto_ptr(), which calls goto_ptr with the pointer
returned by the lookup_tb_ptr() helper. This is the only use case
we have for goto_ptr and lookup_tb_ptr, so having this function is
very convenient. Furthermore, it trivially allows us to avoid calling
the lookup helper if goto_ptr is not implemented by the backend.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1493263764-18657-2-git-send-email-cota@braap.org>
Message-Id: <1493263764-18657-3-git-send-email-cota@braap.org>
Message-Id: <1493263764-18657-4-git-send-email-cota@braap.org>
Message-Id: <1493263764-18657-5-git-send-email-cota@braap.org>
[rth: Squashed 4 related commits.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
stable-2.10
Emilio G. Cota 2017-04-26 23:29:14 -04:00 committed by Richard Henderson
parent 374aae6534
commit cedbcb0152
19 changed files with 85 additions and 4 deletions

View File

@ -309,10 +309,8 @@ static bool tb_cmp(const void *p, const void *d)
return false;
}
static TranslationBlock *tb_htable_lookup(CPUState *cpu,
target_ulong pc,
target_ulong cs_base,
uint32_t flags)
TranslationBlock *tb_htable_lookup(CPUState *cpu, target_ulong pc,
target_ulong cs_base, uint32_t flags)
{
tb_page_addr_t phys_pc;
struct tb_desc desc;

View File

@ -368,6 +368,8 @@ struct TranslationBlock {
void tb_free(TranslationBlock *tb);
void tb_flush(CPUState *cpu);
void tb_phys_invalidate(TranslationBlock *tb, tb_page_addr_t page_addr);
TranslationBlock *tb_htable_lookup(CPUState *cpu, target_ulong pc,
target_ulong cs_base, uint32_t flags);
#if defined(USE_DIRECT_JUMP)

View File

@ -27,6 +27,9 @@
#include "exec/helper-proto.h"
#include "exec/cpu_ldst.h"
#include "exec/exec-all.h"
#include "exec/tb-hash.h"
#include "disas/disas.h"
#include "exec/log.h"
/* 32-bit helpers */
@ -141,6 +144,35 @@ uint64_t HELPER(ctpop_i64)(uint64_t arg)
return ctpop64(arg);
}
void *HELPER(lookup_tb_ptr)(CPUArchState *env, target_ulong addr)
{
CPUState *cpu = ENV_GET_CPU(env);
TranslationBlock *tb;
target_ulong cs_base, pc;
uint32_t flags;
tb = atomic_rcu_read(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(addr)]);
if (likely(tb)) {
cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags);
if (likely(tb->pc == addr && tb->cs_base == cs_base &&
tb->flags == flags)) {
goto found;
}
tb = tb_htable_lookup(cpu, addr, cs_base, flags);
if (likely(tb)) {
atomic_set(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(addr)], tb);
goto found;
}
}
return tcg_ctx.code_gen_epilogue;
found:
qemu_log_mask_and_addr(CPU_LOG_EXEC, addr,
"Chain %p [%d: " TARGET_FMT_lx "] %s\n",
tb->tc_ptr, cpu->cpu_index, addr,
lookup_symbol(addr));
return tb->tc_ptr;
}
void HELPER(exit_atomic)(CPUArchState *env)
{
cpu_loop_exit_atomic(ENV_GET_CPU(env), GETPC());

View File

@ -477,6 +477,14 @@ current TB was linked to this TB. Otherwise execute the next
instructions. Only indices 0 and 1 are valid and tcg_gen_goto_tb may be issued
at most once with each slot index per TB.
* lookup_and_goto_ptr tb_addr
Look up a TB address ('tb_addr') and jump to it if valid. If not valid,
jump to the TCG epilogue to go back to the exec loop.
This operation is optional. If the TCG backend does not implement the
goto_ptr opcode, emitting this op is equivalent to emitting exit_tb(0).
* qemu_ld_i32/i64 t0, t1, flags, memidx
* qemu_st_i32/i64 t0, t1, flags, memidx

View File

@ -77,6 +77,7 @@ typedef enum {
#define TCG_TARGET_HAS_mulsh_i32 0
#define TCG_TARGET_HAS_extrl_i64_i32 0
#define TCG_TARGET_HAS_extrh_i64_i32 0
#define TCG_TARGET_HAS_goto_ptr 0
#define TCG_TARGET_HAS_div_i64 1
#define TCG_TARGET_HAS_rem_i64 1

View File

@ -123,6 +123,7 @@ extern bool use_idiv_instructions;
#define TCG_TARGET_HAS_mulsh_i32 0
#define TCG_TARGET_HAS_div_i32 use_idiv_instructions
#define TCG_TARGET_HAS_rem_i32 0
#define TCG_TARGET_HAS_goto_ptr 0
enum {
TCG_AREG0 = TCG_REG_R6,

View File

@ -107,6 +107,7 @@ extern bool have_popcnt;
#define TCG_TARGET_HAS_muls2_i32 1
#define TCG_TARGET_HAS_muluh_i32 0
#define TCG_TARGET_HAS_mulsh_i32 0
#define TCG_TARGET_HAS_goto_ptr 0
#if TCG_TARGET_REG_BITS == 64
#define TCG_TARGET_HAS_extrl_i64_i32 0

View File

@ -173,6 +173,7 @@ typedef enum {
#define TCG_TARGET_HAS_mulsh_i64 0
#define TCG_TARGET_HAS_extrl_i64_i32 0
#define TCG_TARGET_HAS_extrh_i64_i32 0
#define TCG_TARGET_HAS_goto_ptr 0
#define TCG_TARGET_deposit_i32_valid(ofs, len) ((len) <= 16)
#define TCG_TARGET_deposit_i64_valid(ofs, len) ((len) <= 16)

View File

@ -130,6 +130,7 @@ extern bool use_mips32r2_instructions;
#define TCG_TARGET_HAS_muluh_i32 1
#define TCG_TARGET_HAS_mulsh_i32 1
#define TCG_TARGET_HAS_bswap32_i32 1
#define TCG_TARGET_HAS_goto_ptr 0
#if TCG_TARGET_REG_BITS == 64
#define TCG_TARGET_HAS_add2_i32 0

View File

@ -82,6 +82,7 @@ extern bool have_isa_3_00;
#define TCG_TARGET_HAS_muls2_i32 0
#define TCG_TARGET_HAS_muluh_i32 1
#define TCG_TARGET_HAS_mulsh_i32 1
#define TCG_TARGET_HAS_goto_ptr 0
#if TCG_TARGET_REG_BITS == 64
#define TCG_TARGET_HAS_add2_i32 0

View File

@ -92,6 +92,7 @@ extern uint64_t s390_facilities;
#define TCG_TARGET_HAS_mulsh_i32 0
#define TCG_TARGET_HAS_extrl_i64_i32 0
#define TCG_TARGET_HAS_extrh_i64_i32 0
#define TCG_TARGET_HAS_goto_ptr 0
#define TCG_TARGET_HAS_div2_i64 1
#define TCG_TARGET_HAS_rot_i64 1

View File

@ -123,6 +123,7 @@ extern bool use_vis3_instructions;
#define TCG_TARGET_HAS_muls2_i32 1
#define TCG_TARGET_HAS_muluh_i32 0
#define TCG_TARGET_HAS_mulsh_i32 0
#define TCG_TARGET_HAS_goto_ptr 0
#define TCG_TARGET_HAS_extrl_i64_i32 1
#define TCG_TARGET_HAS_extrh_i64_i32 1

View File

@ -2587,6 +2587,18 @@ void tcg_gen_goto_tb(unsigned idx)
tcg_gen_op1i(INDEX_op_goto_tb, idx);
}
void tcg_gen_lookup_and_goto_ptr(TCGv addr)
{
if (TCG_TARGET_HAS_goto_ptr && !qemu_loglevel_mask(CPU_LOG_TB_NOCHAIN)) {
TCGv_ptr ptr = tcg_temp_new_ptr();
gen_helper_lookup_tb_ptr(ptr, tcg_ctx.tcg_env, addr);
tcg_gen_op1i(INDEX_op_goto_ptr, GET_TCGV_PTR(ptr));
tcg_temp_free_ptr(ptr);
} else {
tcg_gen_exit_tb(0);
}
}
static inline TCGMemOp tcg_canonicalize_memop(TCGMemOp op, bool is64, bool st)
{
/* Trigger the asserts within as early as possible. */

View File

@ -796,6 +796,17 @@ static inline void tcg_gen_exit_tb(uintptr_t val)
*/
void tcg_gen_goto_tb(unsigned idx);
/**
* tcg_gen_lookup_and_goto_ptr() - look up a TB and jump to it if valid
* @addr: Guest address of the target TB
*
* If the TB is not valid, jump to the epilogue.
*
* This operation is optional. If the TCG backend does not implement goto_ptr,
* this op is equivalent to calling tcg_gen_exit_tb() with 0 as the argument.
*/
void tcg_gen_lookup_and_goto_ptr(TCGv addr);
#if TARGET_LONG_BITS == 32
#define tcg_temp_new() tcg_temp_new_i32()
#define tcg_global_reg_new tcg_global_reg_new_i32

View File

@ -193,6 +193,7 @@ DEF(insn_start, 0, 0, TLADDR_ARGS * TARGET_INSN_START_WORDS,
TCG_OPF_NOT_PRESENT)
DEF(exit_tb, 0, 0, 1, TCG_OPF_BB_END)
DEF(goto_tb, 0, 0, 1, TCG_OPF_BB_END)
DEF(goto_ptr, 0, 1, 0, TCG_OPF_BB_END | IMPL(TCG_TARGET_HAS_goto_ptr))
DEF(qemu_ld_i32, 1, TLADDR_ARGS, 1,
TCG_OPF_CALL_CLOBBER | TCG_OPF_SIDE_EFFECTS)

View File

@ -24,6 +24,8 @@ DEF_HELPER_FLAGS_1(clrsb_i64, TCG_CALL_NO_RWG_SE, i64, i64)
DEF_HELPER_FLAGS_1(ctpop_i32, TCG_CALL_NO_RWG_SE, i32, i32)
DEF_HELPER_FLAGS_1(ctpop_i64, TCG_CALL_NO_RWG_SE, i64, i64)
DEF_HELPER_FLAGS_2(lookup_tb_ptr, TCG_CALL_NO_WG_SE, ptr, env, tl)
DEF_HELPER_FLAGS_1(exit_atomic, TCG_CALL_NO_WG, noreturn, env)
#ifdef CONFIG_SOFTMMU

View File

@ -424,6 +424,11 @@ void tcg_prologue_init(TCGContext *s)
qemu_log_unlock();
}
#endif
/* Assert that goto_ptr is implemented completely. */
if (TCG_TARGET_HAS_goto_ptr) {
tcg_debug_assert(s->code_gen_epilogue != NULL);
}
}
void tcg_func_start(TCGContext *s)

View File

@ -699,6 +699,7 @@ struct TCGContext {
extension that allows arithmetic on void*. */
int code_gen_max_blocks;
void *code_gen_prologue;
void *code_gen_epilogue;
void *code_gen_buffer;
size_t code_gen_buffer_size;
void *code_gen_ptr;

View File

@ -85,6 +85,7 @@
#define TCG_TARGET_HAS_muls2_i32 0
#define TCG_TARGET_HAS_muluh_i32 0
#define TCG_TARGET_HAS_mulsh_i32 0
#define TCG_TARGET_HAS_goto_ptr 0
#if TCG_TARGET_REG_BITS == 64
#define TCG_TARGET_HAS_extrl_i64_i32 0