The problem with peephole2 is it uses a naive sliding-window algorithm
and misses many cases. For example:
float a[10000];
float t() { return a[0] + a[8000]; }
is compiled to:
la.local $r13,a
la.local $r12,a+32768
fld.s $f1,$r13,0
fld.s $f0,$r12,-768
fadd.s $f0,$f1,$f0
by trunk. But as we've explained in r14-4851, the following would be
better with -mexplicit-relocs=auto:
pcalau12i $r13,%pc_hi20(a)
pcalau12i $r12,%pc_hi20(a+32000)
fld.s $f1,$r13,%pc_lo12(a)
fld.s $f0,$r12,%pc_lo12(a+32000)
fadd.s $f0,$f1,$f0
However the sliding-window algorithm just won't detect the pcalau12i/fld
pair to be optimized. Use a define_insn_and_split in combine pass will
work around the issue.
gcc/ChangeLog:
* config/loongarch/loongarch.md:
(simple_load<P:mode><LD_AT_LEAST_32_BIT:mode>): New
define_insn_and_split.
(simple_load_off<P:mode><LD_AT_LEAST_32_BIT:mode>): Likewise.
(simple_load_<su>ext<P:mode><SUBDI:mode><GPR:mode>): Likewise.
(simple_load_off<su>ext<P:mode><SUBDI:mode><GPR:mode>):
Likewise.
(simple_store<ST_ANY:mode><P:mode>): Likewise.
(simple_store_off<ST_ANY:mode><P:mode>): Likewise.
(define_peephole2): Remove la.local/[f]ld peepholes.
gcc/testsuite/ChangeLog:
* gcc.target/loongarch/explicit-relocs-auto-single-load-store-2.c:
New test.
---
Bootstrapped & regtested on loongarch64-linux-gnu. Ok for trunk?
gcc/config/loongarch/loongarch.md | 165 +++++++++---------
...explicit-relocs-auto-single-load-store-2.c | 11 ++
2 files changed, 98 insertions(+), 78 deletions(-)
create mode 100644
gcc/testsuite/gcc.target/loongarch/explicit-relocs-auto-single-load-store-2.c
diff --git a/gcc/config/loongarch/loongarch.md
b/gcc/config/loongarch/loongarch.md
index 7b26d15aa4e..4009de408fb 100644
--- a/gcc/config/loongarch/loongarch.md
+++ b/gcc/config/loongarch/loongarch.md
@@ -4033,101 +4033,110 @@ (define_insn "loongarch_crcc_w_<size>_w"
;;
;; And if the pseudo op cannot be relaxed, we'll get a worse result (with
;; 3 instructions).
-(define_peephole2
- [(set (match_operand:P 0 "register_operand")
- (match_operand:P 1 "symbolic_pcrel_operand"))
- (set (match_operand:LD_AT_LEAST_32_BIT 2 "register_operand")
- (mem:LD_AT_LEAST_32_BIT (match_dup 0)))]
- "la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
- && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM) \
- && (peep2_reg_dead_p (2, operands[0]) \
- || REGNO (operands[0]) == REGNO (operands[2]))"
- [(set (match_dup 2)
- (mem:LD_AT_LEAST_32_BIT (lo_sum:P (match_dup 0) (match_dup 1))))]
+(define_insn_and_split "simple_load<P:mode><LD_AT_LEAST_32_BIT:mode>"
+ [(set (match_operand:LD_AT_LEAST_32_BIT 0 "register_operand" "=r,f")
+ (mem:LD_AT_LEAST_32_BIT
+ (match_operand:P 1 "symbolic_pcrel_operand" "")))]
+ "loongarch_pre_reload_split () \
+ && la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
+ && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM)"
+ "#"
+ ""
+ [(set (match_dup 0)
+ (mem:LD_AT_LEAST_32_BIT (lo_sum:P (match_dup 2) (match_dup 1))))]
{
- emit_insn (gen_pcalau12i_gr<P:mode> (operands[0], operands[1]));
+ operands[2] = gen_reg_rtx (Pmode);
+ emit_insn (gen_pcalau12i_gr<P:mode> (operands[2], operands[1]));
})
-(define_peephole2
- [(set (match_operand:P 0 "register_operand")
- (match_operand:P 1 "symbolic_pcrel_operand"))
- (set (match_operand:LD_AT_LEAST_32_BIT 2 "register_operand")
- (mem:LD_AT_LEAST_32_BIT (plus (match_dup 0)
- (match_operand 3 "const_int_operand"))))]
- "la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
- && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM) \
- && (peep2_reg_dead_p (2, operands[0]) \
- || REGNO (operands[0]) == REGNO (operands[2]))"
- [(set (match_dup 2)
- (mem:LD_AT_LEAST_32_BIT (lo_sum:P (match_dup 0) (match_dup 1))))]
+(define_insn_and_split "simple_load_off<P:mode><LD_AT_LEAST_32_BIT:mode>"
+ [(set (match_operand:LD_AT_LEAST_32_BIT 0 "register_operand" "=r,f")
+ (mem:LD_AT_LEAST_32_BIT
+ (plus (match_operand:P 1 "symbolic_pcrel_operand" "")
+ (match_operand 2 "const_int_operand" ""))))]
+ "loongarch_pre_reload_split () \
+ && la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
+ && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM)"
+ "#"
+ ""
+ [(set (match_dup 0)
+ (mem:LD_AT_LEAST_32_BIT (lo_sum:P (match_dup 2) (match_dup 1))))]
{
- operands[1] = plus_constant (Pmode, operands[1], INTVAL (operands[3]));
- emit_insn (gen_pcalau12i_gr<P:mode> (operands[0], operands[1]));
+ HOST_WIDE_INT offset = INTVAL (operands[2]);
+ operands[2] = gen_reg_rtx (Pmode);
+ operands[1] = plus_constant (Pmode, operands[1], offset);
+ emit_insn (gen_pcalau12i_gr<P:mode> (operands[2], operands[1]));
})
-(define_peephole2
- [(set (match_operand:P 0 "register_operand")
- (match_operand:P 1 "symbolic_pcrel_operand"))
- (set (match_operand:GPR 2 "register_operand")
- (any_extend:GPR (mem:SUBDI (match_dup 0))))]
- "la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
- && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM) \
- && (peep2_reg_dead_p (2, operands[0]) \
- || REGNO (operands[0]) == REGNO (operands[2]))"
- [(set (match_dup 2)
- (any_extend:GPR (mem:SUBDI (lo_sum:P (match_dup 0)
- (match_dup 1)))))]
+(define_insn_and_split "simple_load_<su>ext<P:mode><SUBDI:mode><GPR:mode>"
+ [(set (match_operand:GPR 0 "register_operand" "=r")
+ (any_extend:GPR
+ (mem:SUBDI (match_operand:P 1 "symbolic_pcrel_operand" ""))))]
+ "loongarch_pre_reload_split () \
+ && la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
+ && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM)"
+ "#"
+ ""
+ [(set (match_dup 0)
+ (any_extend:GPR
+ (mem:SUBDI (lo_sum:P (match_dup 2) (match_dup 1)))))]
{
- emit_insn (gen_pcalau12i_gr<P:mode> (operands[0], operands[1]));
+ operands[2] = gen_reg_rtx (Pmode);
+ emit_insn (gen_pcalau12i_gr<P:mode> (operands[2], operands[1]));
})
-(define_peephole2
- [(set (match_operand:P 0 "register_operand")
- (match_operand:P 1 "symbolic_pcrel_operand"))
- (set (match_operand:GPR 2 "register_operand")
+(define_insn_and_split
+ "simple_load_off_<su>ext<P:mode><SUBDI:mode><GPR:mode>"
+ [(set (match_operand:GPR 0 "register_operand" "=r")
+ (any_extend:GPR
+ (mem:SUBDI
+ (plus (match_operand:P 1 "symbolic_pcrel_operand" "")
+ (match_operand 2 "const_int_operand" "")))))]
+ "loongarch_pre_reload_split () \
+ && la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
+ && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM)"
+ "#"
+ ""
+ [(set (match_dup 0)
(any_extend:GPR
- (mem:SUBDI (plus (match_dup 0)
- (match_operand 3 "const_int_operand")))))]
- "la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
- && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM) \
- && (peep2_reg_dead_p (2, operands[0]) \
- || REGNO (operands[0]) == REGNO (operands[2]))"
- [(set (match_dup 2)
- (any_extend:GPR (mem:SUBDI (lo_sum:P (match_dup 0)
- (match_dup 1)))))]
+ (mem:SUBDI (lo_sum:P (match_dup 2) (match_dup 1)))))]
{
- operands[1] = plus_constant (Pmode, operands[1], INTVAL (operands[3]));
- emit_insn (gen_pcalau12i_gr<P:mode> (operands[0], operands[1]));
+ HOST_WIDE_INT offset = INTVAL (operands[2]);
+ operands[2] = gen_reg_rtx (Pmode);
+ operands[1] = plus_constant (Pmode, operands[1], offset);
+ emit_insn (gen_pcalau12i_gr<P:mode> (operands[2], operands[1]));
})
-(define_peephole2
- [(set (match_operand:P 0 "register_operand")
- (match_operand:P 1 "symbolic_pcrel_operand"))
- (set (mem:ST_ANY (match_dup 0))
- (match_operand:ST_ANY 2 "register_operand"))]
- "la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
- && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM) \
- && (peep2_reg_dead_p (2, operands[0])) \
- && REGNO (operands[0]) != REGNO (operands[2])"
- [(set (mem:ST_ANY (lo_sum:P (match_dup 0) (match_dup 1))) (match_dup 2))]
+(define_insn_and_split "simple_store<ST_ANY:mode><P:mode>"
+ [(set (mem:ST_ANY (match_operand:P 0 "symbolic_pcrel_operand"))
+ (match_operand:ST_ANY 1 "register_operand" "r,f"))]
+ "loongarch_pre_reload_split () \
+ && la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
+ && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM)"
+ "#"
+ ""
+ [(set (mem:ST_ANY (lo_sum:P (match_dup 2) (match_dup 0))) (match_dup 1))]
{
- emit_insn (gen_pcalau12i_gr<P:mode> (operands[0], operands[1]));
+ operands[2] = gen_reg_rtx (Pmode);
+ emit_insn (gen_pcalau12i_gr<P:mode> (operands[2], operands[0]));
})
-(define_peephole2
- [(set (match_operand:P 0 "register_operand")
- (match_operand:P 1 "symbolic_pcrel_operand"))
- (set (mem:ST_ANY (plus (match_dup 0)
- (match_operand 3 "const_int_operand")))
- (match_operand:ST_ANY 2 "register_operand"))]
- "la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
- && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM) \
- && (peep2_reg_dead_p (2, operands[0])) \
- && REGNO (operands[0]) != REGNO (operands[2])"
- [(set (mem:ST_ANY (lo_sum:P (match_dup 0) (match_dup 1))) (match_dup 2))]
+(define_insn_and_split "simple_store_off<ST_ANY:mode><P:mode>"
+ [(set (mem:ST_ANY
+ (plus (match_operand:P 0 "symbolic_pcrel_operand" "")
+ (match_operand 1 "const_int_operand" "")))
+ (match_operand:ST_ANY 2 "register_operand" "r,f"))]
+ "loongarch_pre_reload_split () \
+ && la_opt_explicit_relocs == EXPLICIT_RELOCS_AUTO \
+ && (TARGET_CMODEL_NORMAL || TARGET_CMODEL_MEDIUM)"
+ "#"
+ ""
+ [(set (mem:ST_ANY (lo_sum:P (match_dup 1) (match_dup 0))) (match_dup 2))]
{
- operands[1] = plus_constant (Pmode, operands[1], INTVAL (operands[3]));
- emit_insn (gen_pcalau12i_gr<P:mode> (operands[0], operands[1]));
+ HOST_WIDE_INT offset = INTVAL (operands[1]);
+ operands[1] = gen_reg_rtx (Pmode);
+ operands[0] = plus_constant (Pmode, operands[0], offset);
+ emit_insn (gen_pcalau12i_gr<P:mode> (operands[1], operands[0]));
})
;; Synchronization instructions.
diff --git
a/gcc/testsuite/gcc.target/loongarch/explicit-relocs-auto-single-load-store-2.c
b/gcc/testsuite/gcc.target/loongarch/explicit-relocs-auto-single-load-store-2.c
new file mode 100644
index 00000000000..42cb966d1e0
--- /dev/null
+++
b/gcc/testsuite/gcc.target/loongarch/explicit-relocs-auto-single-load-store-2.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=loongarch64 -mabi=lp64d -mexplicit-relocs=auto" }
*/
+
+float a[8001];
+float
+t (void)
+{
+ return a[0] + a[8000];
+}
+
+/* { dg-final { scan-assembler-not "la.local" } } */
--
2.43.0
