Middle distance branches between 1KiB and 1MiB may be
implemented with cmp+branch instead of branch+branch.
gcc:
* config/aarch64/aarch64.cc (*aarch64_cb<INT_CMP><GPI>):
Fall back to cmp/cmn + bcond if !far_branch.
Adjust far_branch to 1MiB.
(*aarch64_cb<INT_CMP><SHORT): Fall back to tst+bcond for
EQ/NE if !far_branch. Adjust far_branch to 1MiB.
---
gcc/config/aarch64/aarch64.md | 37 +++++++++++++++++++++++------------
1 file changed, 25 insertions(+), 12 deletions(-)
diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
index b947da977c3..4c9c1f43af2 100644
--- a/gcc/config/aarch64/aarch64.md
+++ b/gcc/config/aarch64/aarch64.md
@@ -876,10 +876,16 @@
(clobber (reg:CC CC_REGNUM))]
"TARGET_CMPBR && aarch64_cb_rhs (<INT_CMP:CODE>, operands[1])"
{
- return (get_attr_far_branch (insn) == FAR_BRANCH_NO)
- ? "cb<INT_CMP:cmp_op>\\t%<w>0, %<w>1, %l2"
- : aarch64_gen_far_branch (operands, 2,
- "cb<INT_CMP:inv_cmp_op>\\t%<w>0, %<w>1, ");
+ if (get_attr_length (insn) == 4)
+ return "cb<INT_CMP:cmp_op>\t%<w>0, %<w>1, %l2";
+ if (get_attr_far_branch (insn) == FAR_BRANCH_YES)
+ return aarch64_gen_far_branch (operands, 2,
+ "cb<INT_CMP:inv_cmp_op>\t%<w>0, %<w>1, ");
+ if (REG_P (operands[1]) || INTVAL (operands[1]) >= 0)
+ output_asm_insn ("cmp\t%<w>0, %<w>1", operands);
+ else
+ output_asm_insn ("cmn\t%<w>0, %<w>1", operands);
+ return "b<INT_CMP:cmp_op>\t%l2";
}
[(set_attr "type" "branch")
(set (attr "length")
@@ -891,9 +897,9 @@
(const_int 8)))
(set (attr "far_branch")
(if_then_else (and (ge (minus (match_dup 2) (pc))
- (const_int BRANCH_LEN_N_1KiB))
+ (const_int BRANCH_LEN_N_1MiB))
(lt (minus (match_dup 2) (pc))
- (const_int BRANCH_LEN_P_1KiB)))
+ (const_int BRANCH_LEN_P_1MiB)))
(const_string "no")
(const_string "yes")))]
)
@@ -908,10 +914,17 @@
(clobber (reg:CC CC_REGNUM))]
"TARGET_CMPBR"
{
- return (get_attr_far_branch (insn) == FAR_BRANCH_NO)
- ? "cb<SHORT:cmpbr_suffix><INT_CMP:cmp_op>\\t%<w>0, %<w>1, %l2"
- : aarch64_gen_far_branch (operands, 2,
- "cb<SHORT:cmpbr_suffix><INT_CMP:inv_cmp_op>\\t%<w>0, %<w>1, ");
+ if (get_attr_length (insn) == 4)
+ return "cb<SHORT:cmpbr_suffix><INT_CMP:cmp_op>\t%<w>0, %<w>1, %l2";
+ if ((<INT_CMP:CODE> == EQ || <INT_CMP:CODE> == NE)
+ && operands[1] == const0_rtx
+ && get_attr_far_branch (insn) == FAR_BRANCH_NO)
+ {
+ operands[1] = GEN_INT (GET_MODE_MASK (<SHORT:MODE>mode));
+ return "tst\t%w0, %1\;b<INT_CMP:cmp_op>\t%l2";
+ }
+ return aarch64_gen_far_branch (operands, 2,
+ "cb<SHORT:cmpbr_suffix><INT_CMP:inv_cmp_op>\t%<w>0, %<w>1, ");
}
[(set_attr "type" "branch")
(set (attr "length")
@@ -923,9 +936,9 @@
(const_int 8)))
(set (attr "far_branch")
(if_then_else (and (ge (minus (match_dup 2) (pc))
- (const_int BRANCH_LEN_N_1KiB))
+ (const_int BRANCH_LEN_N_1MiB))
(lt (minus (match_dup 2) (pc))
- (const_int BRANCH_LEN_P_1KiB)))
+ (const_int BRANCH_LEN_P_1MiB)))
(const_string "no")
(const_string "yes")))]
)
--
2.43.0
