Hi Guys,
I am checking in the patch below to the mainline and 4.6 branch. It
disables the peephole optimizations in the rx.md file that combine a
load followed by a zero- or sign- extend operation. The disabling
only happens at -O3 (or higher) as although the peepholes reduce the
number of instructions they can introduce pipeline stalls that
actually make the program slower. (This is certainly true for the
coremark test).
Cheers
Nick
gcc/ChangeLog
2011-08-09 Nick Clifton <ni...@redhat.com>
* config/rx/rx.md: Disable extender peepholes at -O3.
Index: gcc/config/rx/rx.md
===================================================================
--- gcc/config/rx/rx.md (revision 177584)
+++ gcc/config/rx/rx.md (working copy)
@@ -1598,7 +1598,7 @@
(memex_commutative:SI (match_dup 0)
(match_dup 2)))
(clobber (reg:CC CC_REG))])]
- "peep2_regno_dead_p (2, REGNO (operands[0]))"
+ "peep2_regno_dead_p (2, REGNO (operands[0])) && (optimize < 3 ||
optimize_size)"
[(parallel [(set:SI (match_dup 2)
(memex_commutative:SI (match_dup 2)
(extend_types:SI (match_dup 1))))
@@ -1612,7 +1612,7 @@
(memex_commutative:SI (match_dup 2)
(match_dup 0)))
(clobber (reg:CC CC_REG))])]
- "peep2_regno_dead_p (2, REGNO (operands[0]))"
+ "peep2_regno_dead_p (2, REGNO (operands[0])) && (optimize < 3 ||
optimize_size)"
[(parallel [(set:SI (match_dup 2)
(memex_commutative:SI (match_dup 2)
(extend_types:SI (match_dup 1))))
@@ -1626,7 +1626,7 @@
(memex_noncomm:SI (match_dup 2)
(match_dup 0)))
(clobber (reg:CC CC_REG))])]
- "peep2_regno_dead_p (2, REGNO (operands[0]))"
+ "peep2_regno_dead_p (2, REGNO (operands[0])) && (optimize < 3 ||
optimize_size)"
[(parallel [(set:SI (match_dup 2)
(memex_noncomm:SI (match_dup 2)
(extend_types:SI (match_dup 1))))
@@ -1639,7 +1639,7 @@
(set (match_operand:SI 2 "register_operand")
(memex_nocc:SI (match_dup 0)
(match_dup 2)))]
- "peep2_regno_dead_p (2, REGNO (operands[0]))"
+ "peep2_regno_dead_p (2, REGNO (operands[0])) && (optimize < 3 ||
optimize_size)"
[(set:SI (match_dup 2)
(memex_nocc:SI (match_dup 2)
(extend_types:SI (match_dup 1))))]
@@ -1651,7 +1651,7 @@
(set (match_operand:SI 2 "register_operand")
(memex_nocc:SI (match_dup 2)
(match_dup 0)))]
- "peep2_regno_dead_p (2, REGNO (operands[0]))"
+ "peep2_regno_dead_p (2, REGNO (operands[0])) && (optimize < 3 ||
optimize_size)"
[(set:SI (match_dup 2)
(memex_nocc:SI (match_dup 2)
(extend_types:SI (match_dup 1))))]
@@ -1662,7 +1662,7 @@
(memex_commutative:SI (match_operand:SI 1
"register_operand" "%0")
(extend_types:SI (match_operand:small_int_modes 2
"rx_restricted_mem_operand" "Q"))))
(clobber (reg:CC CC_REG))]
- ""
+ "(optimize < 3 || optimize_size)"
"<memex_commutative:op>\t%<extend_types:letter>2, %0"
[(set_attr "timings" "33")
(set_attr "length" "5")] ;; This length is corrected in
rx_adjust_insn_length
@@ -1673,7 +1673,7 @@
(memex_noncomm:SI (match_operand:SI 1
"register_operand" "0")
(extend_types:SI (match_operand:small_int_modes 2
"rx_restricted_mem_operand" "Q"))))
(clobber (reg:CC CC_REG))]
- ""
+ "(optimize < 3 || optimize_size)"
"<memex_noncomm:op>\t%<extend_types:letter>2, %0"
[(set_attr "timings" "33")
(set_attr "length" "5")] ;; This length is corrected in
rx_adjust_insn_length
@@ -1683,7 +1683,7 @@
[(set (match_operand:SI 0
"register_operand" "=r")
(memex_nocc:SI (match_operand:SI 1
"register_operand" "%0")
(extend_types:SI (match_operand:small_int_modes 2
"rx_restricted_mem_operand" "Q"))))]
- ""
+ "(optimize < 3 || optimize_size)"
"<memex_nocc:op>\t%<extend_types:letter>2, %0"
[(set_attr "timings" "33")
(set_attr "length" "5")] ;; This length is corrected in
rx_adjust_insn_length
@@ -1695,7 +1695,7 @@
(set (reg:CC CC_REG)
(compare:CC (match_operand:SI 2 "register_operand")
(match_dup 0)))]
- "peep2_regno_dead_p (2, REGNO (operands[0]))"
+ "peep2_regno_dead_p (2, REGNO (operands[0])) && (optimize < 3 ||
optimize_size)"
[(set (reg:CC CC_REG)
(compare:CC (match_dup 2)
(extend_types:SI (match_dup 1))))]
@@ -1734,7 +1734,7 @@
[(set (reg:CC CC_REG)
(compare:CC (match_operand:SI 0
"register_operand" "=r")
(extend_types:SI (match_operand:small_int_modes 1
"rx_restricted_mem_operand" "Q"))))]
- ""
+ "(optimize < 3 || optimize_size)"
"cmp\t%<extend_types:letter>1, %0"
[(set_attr "timings" "33")
(set_attr "length" "5")] ;; This length is corrected in
rx_adjust_insn_length
