Hello!
As suggested by Richard S. [1], after the patch that converts subreg:M
(op:N (...)(...)) to op:M (subreg:M (...) subreg:M (...)), we can
remove several peephole2 patterns that handle subregs of PLUS, MINUS
and MULT operators. I have attached RFC prototype patch that will
trigger an ICE when to-be-removed pattern triggers, with the intention
that these patterns wil be removed entirely (An "invalid" pattern was
indeed generated elsewhere, see patch).
2012-10-18 Uros Bizjak <[email protected]>
* config/i386/i386.md (ashift to lea splitter): Split to SImode mult.
(simple lea to add/shift peephole2s): Remove peephole2s that operate
on subregs of DImode operations.
(*mov<mode>_insv_1_rex64): Use gen_int_mode to truncate
const_int RTX to QImode value.
(*movsi_insv_1): Ditto.
The patch was bootstrapped and regression tested on
x86_64-pc-linux-gnu {,-m32} without problems, but I will ask H.J. to
test the patch on x32 before it is committed to mainline SVN.
[1] http://gcc.gnu.org/ml/gcc-patches/2012-09/msg01856.html
Uros.
Index: i386.md
===================================================================
--- i386.md (revision 192873)
+++ i386.md (working copy)
@@ -2704,7 +2704,8 @@
"TARGET_64BIT"
{
if (CONST_INT_P (operands[1]))
- operands[1] = simplify_gen_subreg (QImode, operands[1], <MODE>mode, 0);
+ operands[1] = gen_int_mode (INTVAL (operands[1]), QImode);
+
return "mov{b}\t{%b1, %h0|%h0, %b1}";
}
[(set_attr "type" "imov")
@@ -2718,7 +2719,8 @@
"!TARGET_64BIT"
{
if (CONST_INT_P (operands[1]))
- operands[1] = simplify_gen_subreg (QImode, operands[1], SImode, 0);
+ operands[1] = gen_int_mode (INTVAL (operands[1]), QImode);
+
return "mov{b}\t{%b1, %h0|%h0, %b1}";
}
[(set_attr "type" "imov")
@@ -9600,10 +9602,10 @@
"TARGET_64BIT && reload_completed
&& true_regnum (operands[0]) != true_regnum (operands[1])"
[(set (match_dup 0)
- (zero_extend:DI (subreg:SI (mult:DI (match_dup 1) (match_dup 2)) 0)))]
+ (zero_extend:DI (mult:SI (match_dup 1) (match_dup 2))))]
{
- operands[1] = gen_lowpart (DImode, operands[1]);
- operands[2] = gen_int_mode (1 << INTVAL (operands[2]), DImode);
+ operands[1] = gen_lowpart (SImode, operands[1]);
+ operands[2] = gen_int_mode (1 << INTVAL (operands[2]), SImode);
})
;; This pattern can't accept a variable shift count, since shifts by
@@ -17366,7 +17368,7 @@
&& peep2_regno_dead_p (0, FLAGS_REG)"
[(parallel [(set (match_dup 0) (plus:SI (match_dup 0) (match_dup 2)))
(clobber (reg:CC FLAGS_REG))])]
- "operands[2] = gen_lowpart (SImode, operands[2]);")
+ "gcc_unreachable ();")
(define_peephole2
[(set (match_operand:SI 0 "register_operand")
@@ -17377,7 +17379,7 @@
&& peep2_regno_dead_p (0, FLAGS_REG)"
[(parallel [(set (match_dup 0) (plus:SI (match_dup 0) (match_dup 1)))
(clobber (reg:CC FLAGS_REG))])]
- "operands[1] = gen_lowpart (SImode, operands[1]);")
+ "gcc_unreachable ();")
(define_peephole2
[(set (match_operand:DI 0 "register_operand")
@@ -17413,10 +17415,7 @@
[(parallel [(set (match_dup 0)
(zero_extend:DI (plus:SI (match_dup 2) (match_dup 1))))
(clobber (reg:CC FLAGS_REG))])]
-{
- operands[1] = gen_lowpart (SImode, operands[1]);
- operands[2] = gen_lowpart (SImode, operands[0]);
-})
+ "gcc_unreachable ();")
(define_peephole2
[(set (match_operand:DI 0 "register_operand")
@@ -17428,10 +17427,7 @@
[(parallel [(set (match_dup 0)
(zero_extend:DI (plus:SI (match_dup 2) (match_dup 1))))
(clobber (reg:CC FLAGS_REG))])]
-{
- operands[1] = gen_lowpart (SImode, operands[1]);
- operands[2] = gen_lowpart (SImode, operands[0]);
-})
+ "gcc_unreachable ();")
(define_peephole2
[(set (match_operand:SWI48 0 "register_operand")
@@ -17453,7 +17449,7 @@
&& peep2_regno_dead_p (0, FLAGS_REG)"
[(parallel [(set (match_dup 0) (ashift:SI (match_dup 0) (match_dup 2)))
(clobber (reg:CC FLAGS_REG))])]
- "operands[2] = GEN_INT (exact_log2 (INTVAL (operands[2])));")
+ "gcc_unreachable ();")
(define_peephole2
[(set (match_operand:DI 0 "register_operand")
@@ -17480,10 +17476,7 @@
[(parallel [(set (match_dup 0)
(zero_extend:DI (ashift:SI (match_dup 2) (match_dup 1))))
(clobber (reg:CC FLAGS_REG))])]
-{
- operands[1] = GEN_INT (exact_log2 (INTVAL (operands[1])));
- operands[2] = gen_lowpart (SImode, operands[0]);
-})
+ "gcc_unreachable ();")
;; The ESP adjustments can be done by the push and pop instructions. Resulting
;; code is shorter, since push is only 1 byte, while add imm, %esp is 3 bytes.
