plugins: implement inline operation relative to cpu_index

Instead of working on a fixed memory location, allow to address it based
on cpu_index, an element size and a given offset.
Result address: ptr + offset + cpu_index * element_size.

With this, we can target a member in a struct array from a base pointer.

Current semantic is not modified, thus inline operation still targets
always the same memory location.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240304130036.124418-4-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240305121005.3528075-17-alex.bennee@linaro.org>
This commit is contained in:
Pierrick Bouvier 2024-03-05 12:09:52 +00:00 committed by Alex Bennée
parent 8042e2eadf
commit 62f92b8d97
4 changed files with 67 additions and 19 deletions

View file

@ -133,16 +133,28 @@ static void gen_empty_udata_cb_no_rwg(void)
*/
static void gen_empty_inline_cb(void)
{
TCGv_i32 cpu_index = tcg_temp_ebb_new_i32();
TCGv_ptr cpu_index_as_ptr = tcg_temp_ebb_new_ptr();
TCGv_i64 val = tcg_temp_ebb_new_i64();
TCGv_ptr ptr = tcg_temp_ebb_new_ptr();
tcg_gen_ld_i32(cpu_index, tcg_env,
-offsetof(ArchCPU, env) + offsetof(CPUState, cpu_index));
/* second operand will be replaced by immediate value */
tcg_gen_mul_i32(cpu_index, cpu_index, cpu_index);
tcg_gen_ext_i32_ptr(cpu_index_as_ptr, cpu_index);
tcg_gen_movi_ptr(ptr, 0);
tcg_gen_add_ptr(ptr, ptr, cpu_index_as_ptr);
tcg_gen_ld_i64(val, ptr, 0);
/* pass an immediate != 0 so that it doesn't get optimized away */
tcg_gen_addi_i64(val, val, 0xdeadface);
/* second operand will be replaced by immediate value */
tcg_gen_add_i64(val, val, val);
tcg_gen_st_i64(val, ptr, 0);
tcg_temp_free_ptr(ptr);
tcg_temp_free_i64(val);
tcg_temp_free_ptr(cpu_index_as_ptr);
tcg_temp_free_i32(cpu_index);
}
static void gen_empty_mem_cb(TCGv_i64 addr, uint32_t info)
@ -290,12 +302,37 @@ static TCGOp *copy_const_ptr(TCGOp **begin_op, TCGOp *op, void *ptr)
return op;
}
static TCGOp *copy_ld_i32(TCGOp **begin_op, TCGOp *op)
{
return copy_op(begin_op, op, INDEX_op_ld_i32);
}
static TCGOp *copy_ext_i32_ptr(TCGOp **begin_op, TCGOp *op)
{
if (UINTPTR_MAX == UINT32_MAX) {
op = copy_op(begin_op, op, INDEX_op_mov_i32);
} else {
op = copy_op(begin_op, op, INDEX_op_ext_i32_i64);
}
return op;
}
static TCGOp *copy_add_ptr(TCGOp **begin_op, TCGOp *op)
{
if (UINTPTR_MAX == UINT32_MAX) {
op = copy_op(begin_op, op, INDEX_op_add_i32);
} else {
op = copy_op(begin_op, op, INDEX_op_add_i64);
}
return op;
}
static TCGOp *copy_ld_i64(TCGOp **begin_op, TCGOp *op)
{
if (TCG_TARGET_REG_BITS == 32) {
/* 2x ld_i32 */
op = copy_op(begin_op, op, INDEX_op_ld_i32);
op = copy_op(begin_op, op, INDEX_op_ld_i32);
op = copy_ld_i32(begin_op, op);
op = copy_ld_i32(begin_op, op);
} else {
/* ld_i64 */
op = copy_op(begin_op, op, INDEX_op_ld_i64);
@ -331,6 +368,13 @@ static TCGOp *copy_add_i64(TCGOp **begin_op, TCGOp *op, uint64_t v)
return op;
}
static TCGOp *copy_mul_i32(TCGOp **begin_op, TCGOp *op, uint32_t v)
{
op = copy_op(begin_op, op, INDEX_op_mul_i32);
op->args[2] = tcgv_i32_arg(tcg_constant_i32(v));
return op;
}
static TCGOp *copy_st_ptr(TCGOp **begin_op, TCGOp *op)
{
if (UINTPTR_MAX == UINT32_MAX) {
@ -396,18 +440,17 @@ static TCGOp *append_inline_cb(const struct qemu_plugin_dyn_cb *cb,
TCGOp *begin_op, TCGOp *op,
int *unused)
{
/* const_ptr */
op = copy_const_ptr(&begin_op, op, cb->userp);
/* ld_i64 */
char *ptr = cb->userp;
size_t elem_size = 0;
size_t offset = 0;
op = copy_ld_i32(&begin_op, op);
op = copy_mul_i32(&begin_op, op, elem_size);
op = copy_ext_i32_ptr(&begin_op, op);
op = copy_const_ptr(&begin_op, op, ptr + offset);
op = copy_add_ptr(&begin_op, op);
op = copy_ld_i64(&begin_op, op);
/* add_i64 */
op = copy_add_i64(&begin_op, op, cb->inline_insn.imm);
/* st_i64 */
op = copy_st_i64(&begin_op, op);
return op;
}