diff mbox series

[v4,27/57] tcg/arm: Use full load/store helpers in user-only mode

Message ID 20230503070656.1746170-28-richard.henderson@linaro.org
State Superseded
Headers show
Series tcg: Improve atomicity support | expand

Commit Message

Richard Henderson May 3, 2023, 7:06 a.m. UTC 
Instead of using helper_unaligned_{ld,st}, use the full load/store helpers.
This will allow the fast path to increase alignment to implement atomicity
while not immediately raising an alignment exception.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 tcg/arm/tcg-target.c.inc | 45 ----------------------------------------
 1 file changed, 45 deletions(-)

Comments

Peter Maydell May 5, 2023, 12:15 p.m. UTC | #1 
On Wed, 3 May 2023 at 08:09, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Instead of using helper_unaligned_{ld,st}, use the full load/store helpers.
> This will allow the fast path to increase alignment to implement atomicity
> while not immediately raising an alignment exception.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM
diff mbox series

Patch

diff --git a/tcg/arm/tcg-target.c.inc b/tcg/arm/tcg-target.c.inc
index a02804dd69..eb0542f32e 100644
--- a/tcg/arm/tcg-target.c.inc
+++ b/tcg/arm/tcg-target.c.inc
@@ -1325,7 +1325,6 @@  typedef struct {
     bool index_scratch;
 } HostAddress;
 
-#ifdef CONFIG_SOFTMMU
 static TCGReg ldst_ra_gen(TCGContext *s, const TCGLabelQemuLdst *l, int arg)
 {
     /* We arrive at the slow path via "BLNE", so R14 contains l->raddr. */
@@ -1368,50 +1367,6 @@  static bool tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *lb)
     tcg_out_goto(s, COND_AL, qemu_st_helpers[opc & MO_SIZE]);
     return true;
 }
-#else
-static bool tcg_out_fail_alignment(TCGContext *s, TCGLabelQemuLdst *l)
-{
-    if (!reloc_pc24(l->label_ptr[0], tcg_splitwx_to_rx(s->code_ptr))) {
-        return false;
-    }
-
-    if (TARGET_LONG_BITS == 64) {
-        /* 64-bit target address is aligned into R2:R3. */
-        TCGMovExtend ext[2] = {
-            { .dst = TCG_REG_R2, .dst_type = TCG_TYPE_I32,
-              .src = l->addrlo_reg,
-              .src_type = TCG_TYPE_I32, .src_ext = MO_UL },
-            { .dst = TCG_REG_R3, .dst_type = TCG_TYPE_I32,
-              .src = l->addrhi_reg,
-              .src_type = TCG_TYPE_I32, .src_ext = MO_UL },
-        };
-        tcg_out_movext2(s, &ext[0], &ext[1], TCG_REG_TMP);
-    } else {
-        tcg_out_mov(s, TCG_TYPE_I32, TCG_REG_R1, l->addrlo_reg);
-    }
-    tcg_out_mov(s, TCG_TYPE_PTR, TCG_REG_R0, TCG_AREG0);
-
-    /*
-     * Tail call to the helper, with the return address back inline,
-     * just for the clarity of the debugging traceback -- the helper
-     * cannot return.  We have used BLNE to arrive here, so LR is
-     * already set.
-     */
-    tcg_out_goto(s, COND_AL, (const void *)
-                 (l->is_ld ? helper_unaligned_ld : helper_unaligned_st));
-    return true;
-}
-
-static bool tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *l)
-{
-    return tcg_out_fail_alignment(s, l);
-}
-
-static bool tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *l)
-{
-    return tcg_out_fail_alignment(s, l);
-}
-#endif /* SOFTMMU */
 
 static TCGLabelQemuLdst *prepare_host_addr(TCGContext *s, HostAddress *h,
                                            TCGReg addrlo, TCGReg addrhi,