RE: [PATCH v2 1/2] [APX CFCMOV] Support APX CFCMOV in if_convert pass
Hi,
Gently ping for this.
This version has removed the target hook and added a new optab for cfcmov.
Thanks,
Lingling
From: Kong, Lingling
Sent: Tuesday, June 18, 2024 3:41 PM
To: gcc-patches@gcc.gnu.org
Cc: Alexander Monakov ; Uros Bizjak ;
lingling.ko...@gmail.com; Hongtao Liu ; Jeff Law
; Richard Biener
Subject: [PATCH v2 1/2] [APX CFCMOV] Support APX CFCMOV in if_convert pass
APX CFCMOV feature implements conditionally faulting which means
that all memory faults are suppressed when the condition code
evaluates to false and load or store a memory operand. Now we
could load or store a memory operand may trap or fault for
conditional move.
In middle-end, now we don't support a conditional move if we knew
that a load from A or B could trap or fault. To enable CFCMOV, we
added a new optab.
Conditional move suppress_fault for condition mem store would not
move any arithmetic calculations. For condition mem load now just
support a conditional move one trap mem and one no trap and no mem
cases.
gcc/ChangeLog:
* ifcvt.cc (noce_try_cmove_load_mem_notrap): Allow convert
to cfcmov for conditional load.
(noce_try_cmove_store_mem_notrap): Convert to conditional store.
(noce_process_if_block): Ditto.
* optabs.def (OPTAB_D): New optab.
---
gcc/ifcvt.cc | 246 -
gcc/optabs.def | 1 +
2 files changed, 246 insertions(+), 1 deletion(-)
diff --git a/gcc/ifcvt.cc b/gcc/ifcvt.cc
index 58ed42673e5..65c069b8cc6 100644
--- a/gcc/ifcvt.cc
+++ b/gcc/ifcvt.cc
@@ -783,6 +783,8 @@ static rtx noce_emit_cmove (struct noce_if_info *, rtx,
enum rtx_code, rtx,
rtx, rtx, rtx, rtx = NULL, rtx
= NULL);
static bool noce_try_cmove (struct noce_if_info *);
static bool noce_try_cmove_arith (struct noce_if_info *);
+static bool noce_try_cmove_load_mem_notrap (struct noce_if_info *);
+static bool noce_try_cmove_store_mem_notrap (struct noce_if_info *, rtx *,
rtx);
static rtx noce_get_alt_condition (struct noce_if_info *, rtx, rtx_insn **);
static bool noce_try_minmax (struct noce_if_info *);
static bool noce_try_abs (struct noce_if_info *);
@@ -2401,6 +2403,233 @@ noce_try_cmove_arith (struct noce_if_info *if_info)
return false;
}
+/* When target support suppress memory fault, try more complex cases involving
+ conditional_move's source or dest may trap or fault. */
+
+static bool
+noce_try_cmove_load_mem_notrap (struct noce_if_info *if_info)
+{
+ rtx a = if_info->a;
+ rtx b = if_info->b;
+ rtx x = if_info->x;
+
+ if (MEM_P (x))
+return false;
+ /* Just handle a conditional move from one trap MEM + other non_trap,
+ non mem cases. */
+ if (!(MEM_P (a) ^ MEM_P (b)))
+ return false;
+ bool a_trap = may_trap_or_fault_p (a);
+ bool b_trap = may_trap_or_fault_p (b);
+
+ if (!(a_trap ^ b_trap))
+return false;
+ if (a_trap && !MEM_P (a))
+return false;
+ if (b_trap && !MEM_P (b))
+return false;
+
+ rtx orig_b;
+ rtx_insn *insn_a, *insn_b;
+ bool a_simple = if_info->then_simple;
+ bool b_simple = if_info->else_simple;
+ basic_block then_bb = if_info->then_bb;
+ basic_block else_bb = if_info->else_bb;
+ rtx target;
+ enum rtx_code code;
+ rtx cond = if_info->cond;
+ rtx_insn *ifcvt_seq;
+
+ /* if (test) x = *a; else x = c - d;
+ => x = c - d;
+ if (test)
+ x = *a;
+ */
+
+ code = GET_CODE (cond);
+ insn_a = if_info->insn_a;
+ insn_b = if_info->insn_b;
+ machine_mode x_mode = GET_MODE (x);
+
+ /* Because we only handle one trap MEM + other non_trap, non mem cases,
+ just move one trap MEM always in then_bb. */
+ if (noce_reversed_cond_code (if_info) != UNKNOWN)
+{
+ bool reversep = false;
+ if (b_trap)
+ reversep = true;
+
+ if (reversep)
+ {
+ if (if_info->rev_cond)
+ {
+ cond = if_info->rev_cond;
+ code = GET_CODE (cond);
+ }
+ else
+ code = reversed_comparison_code (cond, if_info->jump);
+ std::swap (a, b);
+ std::swap (insn_a, insn_b);
+ std::swap (a_simple, b_simple);
+ std::swap (then_bb, else_bb);
+ }
+}
+
+ if (then_bb && else_bb
+ && (!bbs_ok_for_cmove_arith (then_bb, else_bb, if_info->orig_x)
+ || !bbs_ok_for_cmove_arith (else_bb, then_bb,
if_info->orig_x)))
+return false;
+
+ start_sequence ();
+
+ /* If one of the blocks is empty then the corresponding B or A value
+ came from the test block. The non-empty complex block that we will
+ emit might clobber the register used by B or A, so move it to a
[PATCH v2 1/2] [APX CFCMOV] Support APX CFCMOV in if_convert pass
APX CFCMOV feature implements conditionally faulting which means
that all memory faults are suppressed when the condition code
evaluates to false and load or store a memory operand. Now we
could load or store a memory operand may trap or fault for
conditional move.
In middle-end, now we don't support a conditional move if we knew
that a load from A or B could trap or fault. To enable CFCMOV, we
added a new optab.
Conditional move suppress_fault for condition mem store would not
move any arithmetic calculations. For condition mem load now just
support a conditional move one trap mem and one no trap and no mem
cases.
gcc/ChangeLog:
* ifcvt.cc (noce_try_cmove_load_mem_notrap): Allow convert
to cfcmov for conditional load.
(noce_try_cmove_store_mem_notrap): Convert to conditional store.
(noce_process_if_block): Ditto.
* optabs.def (OPTAB_D): New optab.
---
gcc/ifcvt.cc | 246 -
gcc/optabs.def | 1 +
2 files changed, 246 insertions(+), 1 deletion(-)
diff --git a/gcc/ifcvt.cc b/gcc/ifcvt.cc
index 58ed42673e5..65c069b8cc6 100644
--- a/gcc/ifcvt.cc
+++ b/gcc/ifcvt.cc
@@ -783,6 +783,8 @@ static rtx noce_emit_cmove (struct noce_if_info *, rtx,
enum rtx_code, rtx,
rtx, rtx, rtx, rtx = NULL, rtx
= NULL);
static bool noce_try_cmove (struct noce_if_info *);
static bool noce_try_cmove_arith (struct noce_if_info *);
+static bool noce_try_cmove_load_mem_notrap (struct noce_if_info *);
+static bool noce_try_cmove_store_mem_notrap (struct noce_if_info *, rtx *,
rtx);
static rtx noce_get_alt_condition (struct noce_if_info *, rtx, rtx_insn **);
static bool noce_try_minmax (struct noce_if_info *);
static bool noce_try_abs (struct noce_if_info *);
@@ -2401,6 +2403,233 @@ noce_try_cmove_arith (struct noce_if_info *if_info)
return false;
}
+/* When target support suppress memory fault, try more complex cases involving
+ conditional_move's source or dest may trap or fault. */
+
+static bool
+noce_try_cmove_load_mem_notrap (struct noce_if_info *if_info)
+{
+ rtx a = if_info->a;
+ rtx b = if_info->b;
+ rtx x = if_info->x;
+
+ if (MEM_P (x))
+return false;
+ /* Just handle a conditional move from one trap MEM + other non_trap,
+ non mem cases. */
+ if (!(MEM_P (a) ^ MEM_P (b)))
+ return false;
+ bool a_trap = may_trap_or_fault_p (a);
+ bool b_trap = may_trap_or_fault_p (b);
+
+ if (!(a_trap ^ b_trap))
+return false;
+ if (a_trap && !MEM_P (a))
+return false;
+ if (b_trap && !MEM_P (b))
+return false;
+
+ rtx orig_b;
+ rtx_insn *insn_a, *insn_b;
+ bool a_simple = if_info->then_simple;
+ bool b_simple = if_info->else_simple;
+ basic_block then_bb = if_info->then_bb;
+ basic_block else_bb = if_info->else_bb;
+ rtx target;
+ enum rtx_code code;
+ rtx cond = if_info->cond;
+ rtx_insn *ifcvt_seq;
+
+ /* if (test) x = *a; else x = c - d;
+ => x = c - d;
+ if (test)
+ x = *a;
+ */
+
+ code = GET_CODE (cond);
+ insn_a = if_info->insn_a;
+ insn_b = if_info->insn_b;
+ machine_mode x_mode = GET_MODE (x);
+
+ /* Because we only handle one trap MEM + other non_trap, non mem cases,
+ just move one trap MEM always in then_bb. */
+ if (noce_reversed_cond_code (if_info) != UNKNOWN)
+{
+ bool reversep = false;
+ if (b_trap)
+ reversep = true;
+
+ if (reversep)
+ {
+ if (if_info->rev_cond)
+ {
+ cond = if_info->rev_cond;
+ code = GET_CODE (cond);
+ }
+ else
+ code = reversed_comparison_code (cond, if_info->jump);
+ std::swap (a, b);
+ std::swap (insn_a, insn_b);
+ std::swap (a_simple, b_simple);
+ std::swap (then_bb, else_bb);
+ }
+}
+
+ if (then_bb && else_bb
+ && (!bbs_ok_for_cmove_arith (then_bb, else_bb, if_info->orig_x)
+ || !bbs_ok_for_cmove_arith (else_bb, then_bb,
if_info->orig_x)))
+return false;
+
+ start_sequence ();
+
+ /* If one of the blocks is empty then the corresponding B or A value
+ came from the test block. The non-empty complex block that we will
+ emit might clobber the register used by B or A, so move it to a pseudo
+ first. */
+
+ rtx tmp_b = NULL_RTX;
+
+ /* Don't move trap mem to a pseudo. */
+ if (!may_trap_or_fault_p (b) && (b_simple || !else_bb))
+tmp_b = gen_reg_rtx (x_mode);
+
+ orig_b = b;
+
+ rtx emit_a = NULL_RTX;
+ rtx emit_b = NULL_RTX;
+ rtx_insn *tmp_insn = NULL;
+ bool modified_in_a = false;
+ bool modified_in_b = false;
+ /* If either operand is complex, load it into a register first.
+ The best way to do this is to
