diff mbox series

[v5,02/30] tcg/i386: Use indexed addressing for softmmu fast path

Message ID 20230506072235.597467-3-richard.henderson@linaro.org
State Superseded
Headers show
Series tcg: Simplify calls to load/store helpers | expand

Commit Message

Richard Henderson May 6, 2023, 7:22 a.m. UTC 
Since tcg_out_{ld,st}_helper_args, the slow path no longer requires
the address argument to be set up by the tlb load sequence.  Use a
plain load for the addend and indexed addressing with the original
input address register.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 tcg/i386/tcg-target.c.inc | 25 ++++++++++---------------
 1 file changed, 10 insertions(+), 15 deletions(-)

Comments

Alex Bennée May 10, 2023, 8:44 a.m. UTC | #1 
Richard Henderson <richard.henderson@linaro.org> writes:

> Since tcg_out_{ld,st}_helper_args, the slow path no longer requires
> the address argument to be set up by the tlb load sequence.  Use a
> plain load for the addend and indexed addressing with the original
> input address register.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
diff mbox series

Patch

diff --git a/tcg/i386/tcg-target.c.inc b/tcg/i386/tcg-target.c.inc
index 237b154194..8752968af2 100644
--- a/tcg/i386/tcg-target.c.inc
+++ b/tcg/i386/tcg-target.c.inc
@@ -1837,7 +1837,8 @@  static bool tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *l)
         tcg_out_sti(s, TCG_TYPE_PTR, (uintptr_t)l->raddr, TCG_REG_ESP, ofs);
     } else {
         tcg_out_mov(s, TCG_TYPE_PTR, tcg_target_call_iarg_regs[0], TCG_AREG0);
-        /* The second argument is already loaded with addrlo.  */
+        tcg_out_mov(s, TCG_TYPE_TL, tcg_target_call_iarg_regs[1],
+                    l->addrlo_reg);
         tcg_out_movi(s, TCG_TYPE_I32, tcg_target_call_iarg_regs[2], oi);
         tcg_out_movi(s, TCG_TYPE_PTR, tcg_target_call_iarg_regs[3],
                      (uintptr_t)l->raddr);
@@ -1910,7 +1911,8 @@  static bool tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *l)
         tcg_out_st(s, TCG_TYPE_PTR, retaddr, TCG_REG_ESP, ofs);
     } else {
         tcg_out_mov(s, TCG_TYPE_PTR, tcg_target_call_iarg_regs[0], TCG_AREG0);
-        /* The second argument is already loaded with addrlo.  */
+        tcg_out_mov(s, TCG_TYPE_TL, tcg_target_call_iarg_regs[1],
+                    l->addrlo_reg);
         tcg_out_mov(s, (s_bits == MO_64 ? TCG_TYPE_I64 : TCG_TYPE_I32),
                     tcg_target_call_iarg_regs[2], l->datalo_reg);
         tcg_out_movi(s, TCG_TYPE_I32, tcg_target_call_iarg_regs[3], oi);
@@ -2083,16 +2085,6 @@  static TCGLabelQemuLdst *prepare_host_addr(TCGContext *s, HostAddress *h,
     tcg_out_modrm_offset(s, OPC_CMP_GvEv + trexw,
                          TCG_REG_L1, TCG_REG_L0, cmp_ofs);
 
-    /*
-     * Prepare for both the fast path add of the tlb addend, and the slow
-     * path function argument setup.
-     */
-    *h = (HostAddress) {
-        .base = TCG_REG_L1,
-        .index = -1
-    };
-    tcg_out_mov(s, ttype, h->base, addrlo);
-
     /* jne slow_path */
     tcg_out_opc(s, OPC_JCC_long + JCC_JNE, 0, 0, 0);
     ldst->label_ptr[0] = s->code_ptr;
@@ -2109,10 +2101,13 @@  static TCGLabelQemuLdst *prepare_host_addr(TCGContext *s, HostAddress *h,
     }
 
     /* TLB Hit.  */
+    tcg_out_ld(s, TCG_TYPE_PTR, TCG_REG_L0, TCG_REG_L0,
+               offsetof(CPUTLBEntry, addend));
 
-    /* add addend(TCG_REG_L0), TCG_REG_L1 */
-    tcg_out_modrm_offset(s, OPC_ADD_GvEv + hrexw, h->base, TCG_REG_L0,
-                         offsetof(CPUTLBEntry, addend));
+    *h = (HostAddress) {
+        .base = addrlo,
+        .index = TCG_REG_L0,
+    };
 #else
     if (a_bits) {
         ldst = new_ldst_label(s);