With the TCG_REG_RA base, we can form any 2G displacement for 64-bit,
which means we only need 4 insns for the 64-bit target instead of 7.
Generate the mtctr and brctr insns once during translation and not
part of ppc_tb_set_jmp_target. This means we can update only 2 insns,
and we can arrange to do that update atomically.
Signed-off-by: Richard Henderson <r...@twiddle.net>
---
tcg/ppc/tcg-target.c | 56 +++++++++++++++++++++++++++++++++++++++++-----------
translate-all.c | 2 ++
2 files changed, 47 insertions(+), 11 deletions(-)
diff --git a/tcg/ppc/tcg-target.c b/tcg/ppc/tcg-target.c
index c83fd9f..61a487d 100644
--- a/tcg/ppc/tcg-target.c
+++ b/tcg/ppc/tcg-target.c
@@ -1244,11 +1244,41 @@ static void tcg_out_brcond2 (TCGContext *s, const
TCGArg *args,
void ppc_tb_set_jmp_target(uintptr_t jmp_addr, uintptr_t addr)
{
- TCGContext s;
+ tcg_insn_unit insn1, insn2;
+ uint64_t pair;
+
+ if (in_range_b(addr - jmp_addr)) {
+ insn1 = B | ((addr - jmp_addr) & 0x3fffffc);
+ insn2 = NOP;
+ } else if (TCG_TARGET_REG_BITS == 32 || addr == (int32_t)addr) {
+ insn1 = ADDIS | TAI(TCG_REG_TMP1, 0, addr >> 16);
+ insn2 = ORI | TAI(TCG_REG_R0, TCG_REG_TMP1, addr);
+ } else {
+ intptr_t diff = addr - (uintptr_t)tb_ret_addr;
+ int16_t lo = diff;
+ int32_t hi = diff - lo;
+
+ assert(hi + lo == diff);
+ insn1 = ADDIS | TAI(TCG_REG_TMP1, TCG_REG_RA, hi >> 16);
+ insn2 = ADDI | TAI(TCG_REG_R0, TCG_REG_TMP1, lo);
+ }
+
+#ifdef HOST_WORDS_BIGENDIAN
+ pair = (uint64_t)insn1 << 32 | insn2;
+#else
+ pair = (uint64_t)insn2 << 32 | insn1;
+#endif
+
+ if (TCG_TARGET_REG_BITS == 64) {
+ *(uint64_t *)jmp_addr = pair;
+ } else {
+ /* In 32-bit mode, we've got to use the fpu to
+ atomically store 8 bytes. */
+ /* ??? With gcc 4.8+, we could use __atomic_store. */
+ __asm volatile("stfdx %0,0,%1" : : "f"(pair), "r"(jmp_addr));
+ }
- s.code_buf = s.code_ptr = (tcg_insn_unit *)jmp_addr;
- tcg_out_b(&s, 0, (tcg_insn_unit *)addr);
- flush_icache_range(jmp_addr, jmp_addr + tcg_current_code_size(&s));
+ flush_icache_range(jmp_addr, jmp_addr + 8);
}
static void tcg_out_call(TCGContext *s, tcg_insn_unit *target)
@@ -1851,14 +1881,18 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc,
const TCGArg *args,
tcg_out_b(s, 0, tb_ret_addr);
break;
case INDEX_op_goto_tb:
- if (s->tb_jmp_offset) {
- /* Direct jump method. */
- s->tb_jmp_offset[args[0]] = tcg_current_code_size(s);
- s->code_ptr += 7;
- } else {
- /* Indirect jump method. */
- tcg_abort();
+ assert(s->tb_jmp_offset != NULL);
+ /* Direct jump method. */
+ /* Align the two insns so we can update them atomically. */
+ if ((intptr_t)s->code_ptr & 4) {
+ tcg_out32(s, NOP);
}
+ s->tb_jmp_offset[args[0]] = tcg_current_code_size(s);
+ /* Max 2 insns to compose address into R0. */
+ s->code_ptr += 2;
+ /* Branch to the address computed. */
+ tcg_out32(s, MTSPR | RS(TCG_REG_R0) | CTR);
+ tcg_out32(s, BCCTR | BO_ALWAYS);
s->tb_next_offset[args[0]] = tcg_current_code_size(s);
break;
case INDEX_op_br:
diff --git a/translate-all.c b/translate-all.c
index 5549a85..6bd8fe8 100644
--- a/translate-all.c
+++ b/translate-all.c
@@ -466,6 +466,8 @@ static inline PageDesc *page_find(tb_page_addr_t index)
host cpu, as used by the TCG implementation of goto_tb. */
#if defined(__x86_64__)
# define MAX_CODE_GEN_BUFFER_SIZE (2ul * 1024 * 1024 * 1024)
+#elif defined(_ARCH_PPC)
+# define MAX_CODE_GEN_BUFFER_SIZE (2ul * 1024 * 1024 * 1024)
#elif defined(__sparc__)
# define MAX_CODE_GEN_BUFFER_SIZE (2ul * 1024 * 1024 * 1024)
#elif defined(__aarch64__)
--
1.9.3
