All of lore.kernel.org
 help / color / mirror / Atom feed
From: Richard Henderson <richard.henderson@linaro.org>
To: qemu-devel@nongnu.org
Subject: [PATCH v6 09/26] tcg/tci: Improve tcg_target_call_clobber_regs
Date: Sun,  2 May 2021 16:57:10 -0700	[thread overview]
Message-ID: <20210502235727.1979457-10-richard.henderson@linaro.org> (raw)
In-Reply-To: <20210502235727.1979457-1-richard.henderson@linaro.org>

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 ee6cdfec71..fb7c927fdf 100644
--- a/tcg/tci/tcg-target.c.inc
+++ b/tcg/tci/tcg-target.c.inc
@@ -812,8 +812,14 @@ 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



  parent reply	other threads:[~2021-05-03  0:07 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-02 23:57 [PATCH v6 00/26] TCI fixes and cleanups Richard Henderson
2021-05-02 23:57 ` [PATCH v6 01/26] tcg: Combine dh_is_64bit and dh_is_signed to dh_typecode Richard Henderson
2021-05-15  9:10   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 02/26] tcg: Add tcg_call_flags Richard Henderson
2021-05-03 21:39   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 03/26] accel/tcg/plugin-gen: Drop inline markers Richard Henderson
2021-05-03 21:40   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 04/26] plugins: Drop tcg_flags from struct qemu_plugin_dyn_cb Richard Henderson
2021-05-16 12:53   ` Philippe Mathieu-Daudé
2021-05-17 16:13     ` Richard Henderson
2021-05-02 23:57 ` [PATCH v6 05/26] accel/tcg: Add tcg call flags to plugins helpers Richard Henderson
2021-05-15  9:02   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 06/26] tcg: Store the TCGHelperInfo in the TCGOp for call Richard Henderson
2021-05-15  9:00   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 07/26] tcg: Add tcg_call_func Richard Henderson
2021-05-03 21:50   ` Philippe Mathieu-Daudé
2021-05-16  1:21     ` Richard Henderson
2021-05-16 12:48       ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 08/26] tcg: Build ffi data structures for helpers Richard Henderson
2021-05-31 18:55   ` Philippe Mathieu-Daudé
2021-06-01 14:33     ` Richard Henderson
2021-05-02 23:57 ` Richard Henderson [this message]
2021-05-02 23:57 ` [PATCH v6 10/26] tcg/tci: Move call-return regs to end of tcg_target_reg_alloc_order Richard Henderson
2021-05-15  9:01   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 11/26] tcg/tci: Use ffi for calls Richard Henderson
2021-06-01  5:18   ` Philippe Mathieu-Daudé
2021-06-01 14:38     ` Richard Henderson
2021-05-02 23:57 ` [PATCH v6 12/26] tcg/tci: Reserve r13 for a temporary Richard Henderson
2021-05-02 23:57 ` [PATCH v6 13/26] tcg/tci: Emit setcond before brcond Richard Henderson
2021-05-02 23:57 ` [PATCH v6 14/26] tcg/tci: Remove tci_write_reg Richard Henderson
2021-05-03 21:53   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 15/26] tcg/tci: Change encoding to uint32_t units Richard Henderson
2021-05-02 23:57 ` [PATCH v6 16/26] tcg/tci: Implement goto_ptr Richard Henderson
2021-05-02 23:57 ` [PATCH v6 17/26] tcg/tci: Implement movcond Richard Henderson
2021-05-15  9:34   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 18/26] tcg/tci: Implement andc, orc, eqv, nand, nor Richard Henderson
2021-05-03 22:13   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 19/26] tcg/tci: Implement extract, sextract Richard Henderson
2021-05-03 22:04   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 20/26] tcg/tci: Implement clz, ctz, ctpop Richard Henderson
2021-05-03 22:10   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 21/26] tcg/tci: Implement mulu2, muls2 Richard Henderson
2021-05-02 23:57 ` [PATCH v6 22/26] tcg/tci: Implement add2, sub2 Richard Henderson
2021-05-02 23:57 ` [PATCH v6 23/26] tcg/tci: Split out tci_qemu_ld, tci_qemu_st Richard Henderson
2021-05-15  8:56   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 24/26] tests/tcg: Increase timeout for TCI Richard Henderson
2021-05-15  9:14   ` Philippe Mathieu-Daudé
2021-05-02 23:57 ` [PATCH v6 25/26] gitlab: Rename ACCEL_CONFIGURE_OPTS to EXTRA_CONFIGURE_OPTS Richard Henderson
2021-05-03 16:21   ` Willian Rampazzo
2021-05-02 23:57 ` [PATCH v6 26/26] gitlab: Enable cross-i386 builds of TCI Richard Henderson
2021-05-03 16:22   ` Willian Rampazzo
2021-05-03  0:30 ` [PATCH v6 00/26] TCI fixes and cleanups no-reply
2021-05-15 11:01 ` Philippe Mathieu-Daudé

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210502235727.1979457-10-richard.henderson@linaro.org \
    --to=richard.henderson@linaro.org \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.