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tcg/aarch64: Use full load/store helpers in user-only mode
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.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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rth7680 committed May 16, 2023
1 parent 552e82a commit 8223ac3
Showing 1 changed file with 0 additions and 35 deletions.
35 changes: 0 additions & 35 deletions tcg/aarch64/tcg-target.c.inc
Expand Up @@ -1595,7 +1595,6 @@ typedef struct {
TCGType index_ext;
} HostAddress;

#ifdef CONFIG_SOFTMMU
static const TCGLdstHelperParam ldst_helper_param = {
.ntmp = 1, .tmp = { TCG_REG_TMP }
};
Expand Down Expand Up @@ -1628,40 +1627,6 @@ static bool tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *lb)
tcg_out_goto(s, lb->raddr);
return true;
}
#else
static void tcg_out_adr(TCGContext *s, TCGReg rd, const void *target)
{
ptrdiff_t offset = tcg_pcrel_diff(s, target);
tcg_debug_assert(offset == sextract64(offset, 0, 21));
tcg_out_insn(s, 3406, ADR, rd, offset);
}

static bool tcg_out_fail_alignment(TCGContext *s, TCGLabelQemuLdst *l)
{
if (!reloc_pc19(l->label_ptr[0], tcg_splitwx_to_rx(s->code_ptr))) {
return false;
}

tcg_out_mov(s, TCG_TYPE_TL, TCG_REG_X1, l->addrlo_reg);
tcg_out_mov(s, TCG_TYPE_PTR, TCG_REG_X0, TCG_AREG0);

/* "Tail call" to the helper, with the return address back inline. */
tcg_out_adr(s, TCG_REG_LR, l->raddr);
tcg_out_goto_long(s, (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 /* CONFIG_SOFTMMU */

/*
* For softmmu, perform the TLB load and compare.
Expand Down

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