[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH v3 39/70] tcg/tci: Improve tcg_target_call_clobber_regs
From: |
Richard Henderson |
Subject: |
[PATCH v3 39/70] tcg/tci: Improve tcg_target_call_clobber_regs |
Date: |
Sun, 7 Feb 2021 18:37:21 -0800 |
The current setting is much too pessimistic. Indicating only
the one or two registers that are actually assigned after a
call should avoid unnecessary movement between the register
array and the stack array.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
tcg/tci/tcg-target.c.inc | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/tcg/tci/tcg-target.c.inc b/tcg/tci/tcg-target.c.inc
index 8d75482546..4dae09deda 100644
--- a/tcg/tci/tcg-target.c.inc
+++ b/tcg/tci/tcg-target.c.inc
@@ -623,8 +623,14 @@ static void tcg_target_init(TCGContext *s)
tcg_target_available_regs[TCG_TYPE_I32] = BIT(TCG_TARGET_NB_REGS) - 1;
/* Registers available for 64 bit operations. */
tcg_target_available_regs[TCG_TYPE_I64] = BIT(TCG_TARGET_NB_REGS) - 1;
- /* TODO: Which registers should be set here? */
- tcg_target_call_clobber_regs = BIT(TCG_TARGET_NB_REGS) - 1;
+ /*
+ * The interpreter "registers" are in the local stack frame and
+ * cannot be clobbered by the called helper functions. However,
+ * the interpreter assumes a 64-bit return value and assigns to
+ * the return value registers.
+ */
+ tcg_target_call_clobber_regs =
+ MAKE_64BIT_MASK(TCG_REG_R0, 64 / TCG_TARGET_REG_BITS);
s->reserved_regs = 0;
tcg_regset_set_reg(s->reserved_regs, TCG_REG_CALL_STACK);
--
2.25.1
- [PATCH v3 21/70] tcg/tci: Split out tci_args_rrrc, (continued)
- [PATCH v3 21/70] tcg/tci: Split out tci_args_rrrc, Richard Henderson, 2021/02/07
- [PATCH v3 17/70] tcg/tci: Rename tci_read_r to tci_read_rval, Richard Henderson, 2021/02/07
- [PATCH v3 22/70] tcg/tci: Split out tci_args_l, Richard Henderson, 2021/02/07
- [PATCH v3 24/70] tcg/tci: Split out tci_args_rrcl and tci_args_rrrrcl, Richard Henderson, 2021/02/07
- [PATCH v3 26/70] tcg/tci: Reuse tci_args_l for calls., Richard Henderson, 2021/02/07
- [PATCH v3 23/70] tcg/tci: Split out tci_args_rrrrrc, Richard Henderson, 2021/02/07
- [PATCH v3 28/70] tcg/tci: Reuse tci_args_l for goto_tb, Richard Henderson, 2021/02/07
- [PATCH v3 31/70] tcg/tci: Clean up deposit operations, Richard Henderson, 2021/02/07
- [PATCH v3 27/70] tcg/tci: Reuse tci_args_l for exit_tb, Richard Henderson, 2021/02/07
- [PATCH v3 33/70] tcg/tci: Split out tci_args_{rrm,rrrm,rrrrm}, Richard Henderson, 2021/02/07
- [PATCH v3 39/70] tcg/tci: Improve tcg_target_call_clobber_regs,
Richard Henderson <=
- [PATCH v3 38/70] tcg/tci: Use ffi for calls, Richard Henderson, 2021/02/07
- [PATCH v3 25/70] tcg/tci: Split out tci_args_ri and tci_args_rI, Richard Henderson, 2021/02/07
- [PATCH v3 37/70] tcg: Build ffi data structures for helpers, Richard Henderson, 2021/02/07
- [PATCH v3 34/70] tcg/tci: Hoist op_size checking into tci_args_*, Richard Henderson, 2021/02/07
- [PATCH v3 36/70] tcg/tci: Implement the disassembler properly, Richard Henderson, 2021/02/07
- [PATCH v3 29/70] tcg/tci: Split out tci_args_rrrrrr, Richard Henderson, 2021/02/07
- [PATCH v3 35/70] tcg/tci: Remove tci_disas, Richard Henderson, 2021/02/07
- [PATCH v3 32/70] tcg/tci: Reduce qemu_ld/st TCGMemOpIdx operand to 32-bits, Richard Henderson, 2021/02/07
- [PATCH v3 30/70] tcg/tci: Split out tci_args_rrrr, Richard Henderson, 2021/02/07
- [PATCH v3 40/70] tcg/tci: Move call-return regs to end of tcg_target_reg_alloc_order, Richard Henderson, 2021/02/07