Hi,
This patch adds doloop_end standard pattern for AArch64 port so that
-fmodulo-sched can do its job.
Reg-tested for aarch64-linux-gnu with QEMU. OK for the trunk?
Index: gcc/ChangeLog
===================================================================
--- gcc/ChangeLog (revision 216838)
+++ gcc/ChangeLog (working copy)
@@ -1,3 +1,7 @@
+2014-11-10 Felix Yang <felix.y...@huawei.com>
+
+ * config/aarch64/aarch64.md (doloop_end): New pattern.
+
2014-10-29 Richard Sandiford <richard.sandif...@arm.com>
* addresses.h, alias.c, asan.c, auto-inc-dec.c, bt-load.c, builtins.c,
Index: gcc/config/aarch64/aarch64.md
===================================================================
--- gcc/config/aarch64/aarch64.md (revision 216838)
+++ gcc/config/aarch64/aarch64.md (working copy)
@@ -4087,6 +4087,48 @@
[(set_attr "type" "mrs")])
+;; Define the subtract-one-and-jump insns so loop.c
+;; knows what to generate.
+(define_expand "doloop_end"
+ [(use (match_operand 0 "" "")) ; loop pseudo
+ (use (match_operand 1 "" ""))] ; label
+ ""
+ "
+{
+ /* Currently SMS relies on the do-loop pattern to recognize loops
+ where (1) the control part consists of all insns defining and/or
+ using a certain 'count' register and (2) the loop count can be
+ adjusted by modifying this register prior to the loop.
+ ??? The possible introduction of a new block to initialize the
+ new IV can potentially affect branch optimizations. */
+ if (optimize > 0 && flag_modulo_sched)
+ {
+ rtx s0;
+ rtx bcomp;
+ rtx loc_ref;
+ rtx cc_reg;
+ rtx insn;
+ rtx cmp;
+
+ if (GET_MODE (operands[0]) != DImode)
+ FAIL;
+
+ s0 = operands [0];
+ insn = emit_insn (gen_adddi3_compare0 (s0, s0, GEN_INT (-1)));
+
+ cmp = XVECEXP (PATTERN (insn), 0, 0);
+ cc_reg = SET_DEST (cmp);
+ bcomp = gen_rtx_NE (VOIDmode, cc_reg, const0_rtx);
+ loc_ref = gen_rtx_LABEL_REF (VOIDmode, operands [1]);
+ emit_jump_insn (gen_rtx_SET (VOIDmode, pc_rtx,
+ gen_rtx_IF_THEN_ELSE (VOIDmode, bcomp,
+ loc_ref, pc_rtx)));
+ DONE;
+ }
+ else
+ FAIL;
+}")
+
;; AdvSIMD Stuff
(include "aarch64-simd.md")
aarch64-doloop-v1.diff
Description: aarch64-doloop-v1.diff
