| Message ID | 20221206041715.314209-23-richard.henderson@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | tcg: exit_tb tidy, goto_tb reorg | expand |
On 6/12/22 05:17, Richard Henderson wrote: > Now that tcg can handle direct and indirect goto_tb simultaneously, > we can optimistically leave space for a direct branch and fall back > to loading the pointer from the TB for an indirect branch. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > tcg/riscv/tcg-target.h | 5 +++++ > tcg/riscv/tcg-target.c.inc | 19 +++++++++++++++++-- > 2 files changed, 22 insertions(+), 2 deletions(-) > > diff --git a/tcg/riscv/tcg-target.h b/tcg/riscv/tcg-target.h > index 56f7bc3346..a75c84f2a6 100644 > --- a/tcg/riscv/tcg-target.h > +++ b/tcg/riscv/tcg-target.h > @@ -159,6 +159,11 @@ typedef enum { > #define TCG_TARGET_HAS_mulsh_i64 1 > #endif > > +<<<<<<< HEAD > +======= > +void tb_target_set_jmp_target(uintptr_t, uintptr_t, uintptr_t, uintptr_t); > + > +>>>>>>> 89ab294271 (tcg/riscv: Implement TCG_TARGET_HAS_direct_jump) HEAD is correct :)
On 12/6/22 01:48, Philippe Mathieu-Daudé wrote: > On 6/12/22 05:17, Richard Henderson wrote: >> Now that tcg can handle direct and indirect goto_tb simultaneously, >> we can optimistically leave space for a direct branch and fall back >> to loading the pointer from the TB for an indirect branch. >> >> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> >> --- >> tcg/riscv/tcg-target.h | 5 +++++ >> tcg/riscv/tcg-target.c.inc | 19 +++++++++++++++++-- >> 2 files changed, 22 insertions(+), 2 deletions(-) >> >> diff --git a/tcg/riscv/tcg-target.h b/tcg/riscv/tcg-target.h >> index 56f7bc3346..a75c84f2a6 100644 >> --- a/tcg/riscv/tcg-target.h >> +++ b/tcg/riscv/tcg-target.h >> @@ -159,6 +159,11 @@ typedef enum { >> #define TCG_TARGET_HAS_mulsh_i64 1 >> #endif >> +<<<<<<< HEAD >> +======= >> +void tb_target_set_jmp_target(uintptr_t, uintptr_t, uintptr_t, uintptr_t); >> + >> +>>>>>>> 89ab294271 (tcg/riscv: Implement TCG_TARGET_HAS_direct_jump) > > HEAD is correct :) Ouch. Clearly didn't get the fixed branch pushed back. I wonder what else I missed... r~
diff --git a/tcg/riscv/tcg-target.h b/tcg/riscv/tcg-target.h index 56f7bc3346..a75c84f2a6 100644 --- a/tcg/riscv/tcg-target.h +++ b/tcg/riscv/tcg-target.h @@ -159,6 +159,11 @@ typedef enum { #define TCG_TARGET_HAS_mulsh_i64 1 #endif +<<<<<<< HEAD +======= +void tb_target_set_jmp_target(uintptr_t, uintptr_t, uintptr_t, uintptr_t); + +>>>>>>> 89ab294271 (tcg/riscv: Implement TCG_TARGET_HAS_direct_jump) #define TCG_TARGET_DEFAULT_MO (0) #define TCG_TARGET_NEED_LDST_LABELS diff --git a/tcg/riscv/tcg-target.c.inc b/tcg/riscv/tcg-target.c.inc index de029d62b4..ee269ea157 100644 --- a/tcg/riscv/tcg-target.c.inc +++ b/tcg/riscv/tcg-target.c.inc @@ -1278,7 +1278,11 @@ static void tcg_out_exit_tb(TCGContext *s, uintptr_t a0) static void tcg_out_goto_tb(TCGContext *s, int which) { - /* indirect jump method */ + /* Direct branch will be patched by tb_target_set_jmp_target. */ + set_jmp_insn_offset(s, which); + tcg_out32(s, OPC_NOP); + + /* When branch is out of range, fall through to indirect. */ tcg_out_ld(s, TCG_TYPE_PTR, TCG_REG_TMP0, TCG_REG_ZERO, get_jmp_target_addr(s, which)); tcg_out_opc_imm(s, OPC_JALR, TCG_REG_ZERO, TCG_REG_TMP0, 0); @@ -1288,7 +1292,18 @@ static void tcg_out_goto_tb(TCGContext *s, int which) void tb_target_set_jmp_target(const TranslationBlock *tb, int n, uintptr_t jmp_rx, uintptr_t jmp_rw) { - /* Always indirect, nothing to do */ + uintptr_t addr = tb->jmp_target_addr[n]; + ptrdiff_t offset = addr - jmp_rx; + tcg_insn_unit insn; + + /* Either directly branch, or fall through to indirect branch. */ + if (offset == sextreg(offset, 0, 20)) { + insn = encode_uj(OPC_JAL, TCG_REG_ZERO, offset); + } else { + insn = OPC_NOP; + } + qatomic_set((uint32_t *)jmp_rw, insn); + flush_idcache_range(jmp_rx, jmp_rw, 4); } static void tcg_out_op(TCGContext *s, TCGOpcode opc,
Now that tcg can handle direct and indirect goto_tb simultaneously, we can optimistically leave space for a direct branch and fall back to loading the pointer from the TB for an indirect branch. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- tcg/riscv/tcg-target.h | 5 +++++ tcg/riscv/tcg-target.c.inc | 19 +++++++++++++++++-- 2 files changed, 22 insertions(+), 2 deletions(-)