From: lifang_xia@linux.alibaba.com
To: binutils@sourceware.org
Cc: nelson@rivosinc.com, gkm@rivosinc.com, palmer@rivosinc.com,
Lifang Xia <lifang_xia@linux.alibaba.com>
Subject: [PATCH v2] RISC-V: Optimize relax of GP/call with max_alignment.
Date: Thu, 27 Oct 2022 11:19:15 +0800 [thread overview]
Message-ID: <20221027031915.4013-1-lifang_xia@linux.alibaba.com> (raw)
In-Reply-To: <eea67c16-bd5b-daf8-ad7d-997c9ab06183@linux.alibaba.com>
From: Lifang Xia <lifang_xia@linux.alibaba.com>
The max_alignment defined out of [gp-2K, gp+2k), the max_alignment
shouldn't affect the relax of gp.
If the symbol is in [gp-2K, gp+2k), the max_alignment would be
replaced with the max_alignment of the section in [gp-2k, gp+2k).
Likewise, the max_alignment defined out of [call-1M, call+1M),
the max_alignment shouldn't affect the relax of call.
If the symbol is in [call-1M, call+1M), the max_alignment would be
replaced with the max_alignment of the section in [call-1M, call+1M).
bfd/
* elfnn-riscv.c (_bfd_riscv_get_max_alignment_in_jtype): New.
(_bfd_riscv_relax_call): The max_alignment of sections is from
[base-1M, base+1M).
(_bfd_riscv_get_max_alignment_in_itype): New.
(_bfd_riscv_relax_lui): The max_alignment of sections is from
[gp-2K, gp+2K).
(_bfd_riscv_relax_pc): Likewise.
ld/
* ld/testsuite/ld-riscv-elf/relax-max-align-call.*: New tests.
* ld/testsuite/ld-riscv-elf/relax-max-align-gp.*: New tests.
---
bfd/elfnn-riscv.c | 67 +++++++++++++++++++
ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp | 2 +
.../ld-riscv-elf/relax-max-align-call.d | 18 +++++
.../ld-riscv-elf/relax-max-align-call.ld | 22 ++++++
.../ld-riscv-elf/relax-max-align-call.s | 23 +++++++
.../ld-riscv-elf/relax-max-align-gp.d | 46 +++++++++++++
.../ld-riscv-elf/relax-max-align-gp.s | 29 ++++++++
7 files changed, 207 insertions(+)
create mode 100644 ld/testsuite/ld-riscv-elf/relax-max-align-call.d
create mode 100644 ld/testsuite/ld-riscv-elf/relax-max-align-call.ld
create mode 100644 ld/testsuite/ld-riscv-elf/relax-max-align-call.s
create mode 100644 ld/testsuite/ld-riscv-elf/relax-max-align-gp.d
create mode 100644 ld/testsuite/ld-riscv-elf/relax-max-align-gp.s
diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c
index cf852636c9c..ed72704bd80 100644
--- a/bfd/elfnn-riscv.c
+++ b/bfd/elfnn-riscv.c
@@ -4266,6 +4266,28 @@ typedef bool (*relax_func_t) (bfd *, asection *, asection *,
riscv_pcgp_relocs *,
bool undefined_weak);
+/* Traverse all output sections in jtype, and return the max alignment. */
+
+static bfd_vma
+_bfd_riscv_get_max_alignment_in_jtype (asection *sec, bfd_vma base)
+{
+ unsigned int max_alignment_power = 0;
+ asection *o;
+
+ if (sec == NULL)
+ return 0;
+
+ for (o = sec->owner->sections; o != NULL; o = o->next)
+ {
+ if (VALID_JTYPE_IMM (sec_addr(o) - base)
+ || VALID_ITYPE_IMM (sec_addr(o) + o->size - base))
+ if (o->alignment_power > max_alignment_power)
+ max_alignment_power = o->alignment_power;
+ }
+
+ return (bfd_vma) 1 << max_alignment_power;
+}
+
/* Relax AUIPC + JALR into JAL. */
static bool
@@ -4294,6 +4316,15 @@ _bfd_riscv_relax_call (bfd *abfd, asection *sec, asection *sym_sec,
if (sym_sec->output_section == sec->output_section
&& sym_sec->output_section != bfd_abs_section_ptr)
max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power;
+ else
+ {
+ bfd_vma new_max_alignment =
+ _bfd_riscv_get_max_alignment_in_jtype (sec,
+ (sec_addr (sec)
+ + rel->r_offset));
+ if (new_max_alignment)
+ max_alignment = new_max_alignment;
+ }
foff += ((bfd_signed_vma) foff < 0 ? -max_alignment : max_alignment);
}
@@ -4360,6 +4391,28 @@ _bfd_riscv_get_max_alignment (asection *sec)
return (bfd_vma) 1 << max_alignment_power;
}
+/* Traverse all output sections in [gp-2K, gp+2K) and return the max alignment. */
+
+static bfd_vma
+_bfd_riscv_get_max_alignment_in_itype (asection *sec, bfd_vma gp)
+{
+ unsigned int max_alignment_power = 0;
+ asection *o;
+
+ if (sec == NULL)
+ return 0;
+
+ for (o = sec->owner->sections; o != NULL; o = o->next)
+ {
+ if (VALID_ITYPE_IMM (sec_addr(o) - gp)
+ || VALID_ITYPE_IMM (sec_addr(o) + o->size - gp))
+ if (o->alignment_power > max_alignment_power)
+ max_alignment_power = o->alignment_power;
+ }
+
+ return (bfd_vma) 1 << max_alignment_power;
+}
+
/* Relax non-PIC global variable references to GP-relative references. */
static bool
@@ -4391,6 +4444,13 @@ _bfd_riscv_relax_lui (bfd *abfd,
if (h->u.def.section->output_section == sym_sec->output_section
&& sym_sec->output_section != bfd_abs_section_ptr)
max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power;
+ else
+ {
+ /* Otherwise, consider the alignment of sections in [gp-2K,gp+2K). */
+ bfd_vma new_max_alignment = _bfd_riscv_get_max_alignment_in_itype (sec, gp);
+ if (new_max_alignment)
+ max_alignment = new_max_alignment;
+ }
}
/* Is the reference in range of x0 or gp?
@@ -4656,6 +4716,13 @@ _bfd_riscv_relax_pc (bfd *abfd ATTRIBUTE_UNUSED,
if (h->u.def.section->output_section == sym_sec->output_section
&& sym_sec->output_section != bfd_abs_section_ptr)
max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power;
+ else if (!undefined_weak)
+ {
+ /* Otherwise, consider the alignment of sections in [gp-2K,gp+2K). */
+ bfd_vma new_max_alignment = _bfd_riscv_get_max_alignment_in_itype (sec, gp);
+ if (new_max_alignment)
+ max_alignment = new_max_alignment;
+ }
}
/* Is the reference in range of x0 or gp?
diff --git a/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp b/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
index df89e0ee68b..f38807b991e 100644
--- a/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
+++ b/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
@@ -169,6 +169,8 @@ if [istarget "riscv*-*-*"] {
run_dump_test "attr-merge-priv-spec-failed-05"
run_dump_test "attr-merge-priv-spec-failed-06"
run_dump_test "attr-phdr"
+ run_dump_test "relax-max-align-gp"
+ run_dump_test "relax-max-align-call"
run_ld_link_tests [list \
[list "Weak reference 32" "-T weakref.ld -m[riscv_choose_ilp32_emul]" "" \
"-march=rv32i -mabi=ilp32" {weakref32.s} \
diff --git a/ld/testsuite/ld-riscv-elf/relax-max-align-call.d b/ld/testsuite/ld-riscv-elf/relax-max-align-call.d
new file mode 100644
index 00000000000..490ad8c865e
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/relax-max-align-call.d
@@ -0,0 +1,18 @@
+#source: relax-max-align-call.s
+#as: -march=rv64gc
+#ld: -Trelax-max-align-call.ld
+#objdump: -d
+
+.*:[ ]+file format .*
+
+
+Disassembly of section .text1:
+
+0000000000100000 <_start>:
+[ ]+100000:[ ]+79dff0ef[ ]+jal[ ]+1fff9c <foo>
+[ ]+100004:[ ]+a001[ ]+j[ ]+100004 <_start\+0x4>
+
+Disassembly of section .text2:
+
+00000000001fff9c <foo>:
+[ ]+1fff9c:[ ]+8082[ ]+ret
diff --git a/ld/testsuite/ld-riscv-elf/relax-max-align-call.ld b/ld/testsuite/ld-riscv-elf/relax-max-align-call.ld
new file mode 100644
index 00000000000..91991ed0f41
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/relax-max-align-call.ld
@@ -0,0 +1,22 @@
+
+ENTRY(_start)
+
+SECTIONS
+{
+ . = 0x100000;
+
+ .text1 : {
+ *(.text1)
+ }
+
+ . = 0x200000 - 100;
+
+ .text2 : {
+ *(.text2)
+ }
+
+ . = 0x300000;
+ .data : {
+ *(.data)
+ }
+}
diff --git a/ld/testsuite/ld-riscv-elf/relax-max-align-call.s b/ld/testsuite/ld-riscv-elf/relax-max-align-call.s
new file mode 100644
index 00000000000..3335c0970e7
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/relax-max-align-call.s
@@ -0,0 +1,23 @@
+
+.section .text1, "ax"
+.global _start
+.align 2
+_start:
+ call foo
+ j .
+ .size _start, . - _start
+
+.section .text2, "ax"
+.align 2
+.global foo
+.type foo, @function
+foo:
+ ret
+ .size foo, . - foo
+
+.data
+.global gdata
+.align 10
+gdata:
+ .long 0
+ .size gdata, . - gdata
diff --git a/ld/testsuite/ld-riscv-elf/relax-max-align-gp.d b/ld/testsuite/ld-riscv-elf/relax-max-align-gp.d
new file mode 100644
index 00000000000..637de426ee4
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/relax-max-align-gp.d
@@ -0,0 +1,46 @@
+#source: relax-max-align-gp.s
+#ld:
+#objdump: -d
+
+.*:[ ]+file format .*
+
+
+Disassembly of section .text:
+
+0+[0-9a-f]+ <_start>:
+.*:[ ]+[0-9a-f]+[ ]+add[ ]+.*<gdata>
+.*:[ ]+[0-9a-f]+[ ]+jal[ ]+.*
+.*:[ ]+[0-9a-f]+[ ]+j[ ]+.*
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+.*:[ ]+[0-9a-f]+[ ]+nop
+
+0+[0-9a-f]+ <func>:
+.*:[ ]+[0-9a-f]+[ ]+ret
+[ ]+...
diff --git a/ld/testsuite/ld-riscv-elf/relax-max-align-gp.s b/ld/testsuite/ld-riscv-elf/relax-max-align-gp.s
new file mode 100644
index 00000000000..0d162ff4d93
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/relax-max-align-gp.s
@@ -0,0 +1,29 @@
+
+.global _start
+_start:
+ lui a0, %hi(gdata)
+ addi a0, a0, %lo(gdata)
+ call func
+ j .
+ .size _start, . - _start
+
+.global func
+.align 7
+func:
+ ret
+ .size func, . - func
+
+.data
+padding:
+ .long 0
+ .long 0
+ .long 0
+ .long 0
+ .size padding, . - padding
+
+.global gdata
+.type gdata, object
+gdata:
+ .zero 4
+ .size gdata, . - gdata
+
--
2.37.0 (Apple Git-136)
next prev parent reply other threads:[~2022-10-27 3:19 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-23 6:47 [PATCH] RISC-V: Optimize relax of GP " lifang_xia
2022-09-23 8:05 ` Nelson Chu
2022-09-23 9:09 ` Lifang Xia
2022-09-23 9:46 ` lifang_xia
2022-09-23 10:44 ` Nelson Chu
2022-09-24 1:54 ` Lifang Xia
2022-09-27 8:51 ` Nelson Chu
2022-10-27 3:19 ` lifang_xia [this message]
2022-11-09 2:52 ` [PATCH v2] RISC-V: Optimize relax of GP/call " Lifang Xia
2022-11-22 10:19 ` Nelson Chu
2022-11-22 16:19 ` Palmer Dabbelt
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