Hi all:
Sorry for repeat patch content in last mail, here is the clean version
for this patch.
diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h
index 7ca47a7..1638332 100644
--- a/gcc/config/arm/arm.h
+++ b/gcc/config/arm/arm.h
@@ -1152,7 +1152,7 @@ extern int arm_regs_in_sequence[];
/* Tell IRA to use the order we define rather than messing it up with its
own cost calculations. */
-#define HONOR_REG_ALLOC_ORDER
+#define HONOR_REG_ALLOC_ORDER 1
/* Interrupt functions can only use registers that have already been
saved by the prologue, even if they would normally be
diff --git a/gcc/config/nds32/nds32.h b/gcc/config/nds32/nds32.h
index 38847e5..8f966ec 100644
--- a/gcc/config/nds32/nds32.h
+++ b/gcc/config/nds32/nds32.h
@@ -553,7 +553,7 @@ enum nds32_builtins
/* Tell IRA to use the order we define rather than messing it up with its
own cost calculations. */
-#define HONOR_REG_ALLOC_ORDER
+#define HONOR_REG_ALLOC_ORDER 1
/* The number of consecutive hard regs needed starting at
reg "regno" for holding a value of mode "mode". */
diff --git a/gcc/defaults.h b/gcc/defaults.h
index f94ae17..1c48759 100644
--- a/gcc/defaults.h
+++ b/gcc/defaults.h
@@ -1085,6 +1085,10 @@ see the files COPYING3 and COPYING.RUNTIME
respectively. If not, see
#define LOCAL_REGNO(REGNO) 0
#endif
+#ifndef HONOR_REG_ALLOC_ORDER
+#define HONOR_REG_ALLOC_ORDER 0
+#endif
+
/* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
the stack pointer does not matter. The value is tested only in
functions that have frame pointers. */
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
index f204936..c0de478 100644
--- a/gcc/doc/tm.texi
+++ b/gcc/doc/tm.texi
@@ -2044,8 +2044,8 @@ Normally, IRA tries to estimate the costs for
saving a register in the
prologue and restoring it in the epilogue. This discourages it from
using call-saved registers. If a machine wants to ensure that IRA
allocates registers in the order given by REG_ALLOC_ORDER even if some
-call-saved registers appear earlier than call-used ones, this macro
-should be defined.
+call-saved registers appear earlier than call-used ones, then define this
+ macro as a C expression to nonzero. Default is 0.
@end defmac
@defmac IRA_HARD_REGNO_ADD_COST_MULTIPLIER (@var{regno})
diff --git a/gcc/doc/tm.texi.in b/gcc/doc/tm.texi.in
index 50f412c..d7ae6a7 100644
--- a/gcc/doc/tm.texi.in
+++ b/gcc/doc/tm.texi.in
@@ -1849,8 +1849,8 @@ Normally, IRA tries to estimate the costs for
saving a register in the
prologue and restoring it in the epilogue. This discourages it from
using call-saved registers. If a machine wants to ensure that IRA
allocates registers in the order given by REG_ALLOC_ORDER even if some
-call-saved registers appear earlier than call-used ones, this macro
-should be defined.
+call-saved registers appear earlier than call-used ones, then define this
+ macro as a C expression to nonzero. Default is 0.
@end defmac
@defmac IRA_HARD_REGNO_ADD_COST_MULTIPLIER (@var{regno})
diff --git a/gcc/ira-color.c b/gcc/ira-color.c
index c20aaf7..773c86e 100644
--- a/gcc/ira-color.c
+++ b/gcc/ira-color.c
@@ -1599,7 +1599,6 @@ check_hard_reg_p (ira_allocno_t a, int hard_regno,
}
return j == nregs;
}
-#ifndef HONOR_REG_ALLOC_ORDER
/* Return number of registers needed to be saved and restored at
function prologue/epilogue if we allocate HARD_REGNO to hold value
@@ -1618,7 +1617,6 @@ calculate_saved_nregs (int hard_regno, enum
machine_mode mode)
nregs++;
return nregs;
}
-#endif
/* Choose a hard register for allocno A. If RETRY_P is TRUE, it means
that the function called from function
@@ -1653,11 +1651,9 @@ assign_hard_reg (ira_allocno_t a, bool retry_p)
enum reg_class aclass;
enum machine_mode mode;
static int costs[FIRST_PSEUDO_REGISTER], full_costs[FIRST_PSEUDO_REGISTER];
-#ifndef HONOR_REG_ALLOC_ORDER
int saved_nregs;
enum reg_class rclass;
int add_cost;
-#endif
#ifdef STACK_REGS
bool no_stack_reg_p;
#endif
@@ -1823,19 +1819,21 @@ assign_hard_reg (ira_allocno_t a, bool retry_p)
continue;
cost = costs[i];
full_cost = full_costs[i];
-#ifndef HONOR_REG_ALLOC_ORDER
- if ((saved_nregs = calculate_saved_nregs (hard_regno, mode)) != 0)
- /* We need to save/restore the hard register in
- epilogue/prologue. Therefore we increase the cost. */
- {
- rclass = REGNO_REG_CLASS (hard_regno);
- add_cost = ((ira_memory_move_cost[mode][rclass][0]
- + ira_memory_move_cost[mode][rclass][1])
- * saved_nregs / hard_regno_nregs[hard_regno][mode] - 1);
- cost += add_cost;
- full_cost += add_cost;
- }
-#endif
+
+ if (!HONOR_REG_ALLOC_ORDER) {
+ if ((saved_nregs = calculate_saved_nregs (hard_regno, mode)) != 0)
+ /* We need to save/restore the hard register in
+ epilogue/prologue. Therefore we increase the cost. */
+ {
+ rclass = REGNO_REG_CLASS (hard_regno);
+ add_cost = ((ira_memory_move_cost[mode][rclass][0]
+ + ira_memory_move_cost[mode][rclass][1])
+ * saved_nregs / hard_regno_nregs[hard_regno][mode] - 1);
+ cost += add_cost;
+ full_cost += add_cost;
+ }
+ }
+
if (min_cost > cost)
min_cost = cost;
if (min_full_cost > full_cost)
On Wed, Feb 26, 2014 at 11:47 PM, Kito Cheng <kito@0xlab.org> wrote:
This patch change the usage for HONOR_REG_ALLOC_ORDER, currently it's
can define or not define only. it's determine how cost caculate in
register allocation during gcc build time, and can't change it during
compile time.
However in some target, define HONOR_REG_ALLOC_ORDER is good for
optimize code size but get worse for performance such as nds32.
so I think make it's became a C expression style marco is the
solution, let back-end decide when we need HONOR_REG_ALLOC_ORDER
instead of decide it during build time.
2014-02-26 Kito Cheng <kito@0xlab.org>
* defaults.h (HONOR_REG_ALLOC_ORDER): Change HONOR_REG_ALLOC_ORDER
to a C expression marco.
* ira-color.c (HONOR_REG_ALLOC_ORDER) : Ditto.
* config/arm/arm.h (HONOR_REG_ALLOC_ORDER): Ditto.
* config/nds32/nds32.h (HONOR_REG_ALLOC_ORDER): Ditto.
* doc/tm.texi (HONOR_REG_ALLOC_ORDER): Update document for
HONOR_REG_ALLOC_ORDER.
* doc/tm.texi.in (HONOR_REG_ALLOC_ORDER): Ditto.