From: mengqinggang <mengqinggang@loongson.cn>
To: binutils@sourceware.org
Cc: xuchenghua@loongson.cn, chenglulu@loongson.cn,
liuzhensong@loongson.cn, cailulu@loongson.cn, xry111@xry111.site,
i.swmail@xen0n.name, maskray@google.com, luweining@loongson.cn,
wanglei@loongson.cn, hejinyang@loongson.cn,
mengqinggang@loongson.cn
Subject: [PATCH v2] LoongArch: gas: Try to avoid R_LARCH_ALIGN associate with a symbol
Date: Thu, 22 Feb 2024 20:42:32 +0800 [thread overview]
Message-ID: <20240222124232.2925221-1-mengqinggang@loongson.cn> (raw)
The R_LARCH_ALIGN need to associated with a symbol if .align has the first
and third expressions. If R_LARCH_ALIGN associate with a symbol, the addend can
represent the first and third expression of .align.
For '.align 3', the addend of R_LARCH_ALIGN only need to represent the alignment
and R_LARCH_ALIGN not need to associate with a symbol.
For '.align x, , y', R_LARCH_ALIGN need to associate with a symbol if 0 < y <
2^x - 4.
---
v1 -> v2:
- For '.align x, , y', R_LARCH_ALIGN need to associate with a symbol if 0 < y <
2^x - 4.
v1 link: https://sourceware.org/pipermail/binutils/2024-February/132306.html
gas/config/tc-loongarch.c | 27 +++++++---
gas/testsuite/gas/loongarch/relax_align.d | 64 +++++++++++++----------
gas/testsuite/gas/loongarch/relax_align.s | 20 +++++--
3 files changed, 72 insertions(+), 39 deletions(-)
diff --git a/gas/config/tc-loongarch.c b/gas/config/tc-loongarch.c
index 91f5f1d0681..de92366eda4 100644
--- a/gas/config/tc-loongarch.c
+++ b/gas/config/tc-loongarch.c
@@ -1746,14 +1746,25 @@ loongarch_frag_align_code (int n, int max)
nops = frag_more (worst_case_bytes);
- s = symbol_find (".Lla-relax-align");
- if (s == NULL)
- s = (symbolS *)local_symbol_make (".Lla-relax-align", now_seg,
- &zero_address_frag, 0);
-
- ex.X_add_symbol = s;
- ex.X_op = O_symbol;
- ex.X_add_number = (max << 8) | n;
+ /* If max <= 0, ignore max.
+ If max >= worst_case_bytes, max has no effect.
+ Similar to gas/write.c relax_segment function rs_align_code case:
+ if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype). */
+ if (max > 0 && (bfd_vma) max < worst_case_bytes)
+ {
+ s = symbol_find (".Lla-relax-align");
+ if (s == NULL)
+ s = (symbolS *)local_symbol_make (".Lla-relax-align", now_seg,
+ &zero_address_frag, 0);
+ ex.X_add_symbol = s;
+ ex.X_op = O_symbol;
+ ex.X_add_number = (max << 8) | n;
+ }
+ else
+ {
+ ex.X_op = O_constant;
+ ex.X_add_number = worst_case_bytes;
+ }
loongarch_make_nops (nops, worst_case_bytes);
diff --git a/gas/testsuite/gas/loongarch/relax_align.d b/gas/testsuite/gas/loongarch/relax_align.d
index 2cc6c86d38a..fc1fd032611 100644
--- a/gas/testsuite/gas/loongarch/relax_align.d
+++ b/gas/testsuite/gas/loongarch/relax_align.d
@@ -1,4 +1,4 @@
-#as: --no-warn
+#as:
#objdump: -dr
#skip: loongarch32-*-*
@@ -8,29 +8,39 @@
Disassembly of section .text:
[ ]*0000000000000000 <.Lla-relax-align>:
-[ ]+0:[ ]+1a000004[ ]+pcalau12i[ ]+\$a0, 0
-[ ]+0: R_LARCH_PCALA_HI20[ ]+L1
-[ ]+0: R_LARCH_RELAX[ ]+\*ABS\*
-[ ]+4:[ ]+02c00084[ ]+addi.d[ ]+\$a0, \$a0, 0
-[ ]+4: R_LARCH_PCALA_LO12[ ]+L1
-[ ]+4: R_LARCH_RELAX[ ]+\*ABS\*
-[ ]+8:[ ]+03400000[ ]+nop.*
-[ ]+8: R_LARCH_ALIGN[ ]+.Lla-relax-align\+0x4
-[ ]+c:[ ]+03400000[ ]+nop.*
-[ ]+10:[ ]+03400000[ ]+nop.*
-[ ]+14:[ ]+1a000004[ ]+pcalau12i[ ]+\$a0, 0
-[ ]+14: R_LARCH_PCALA_HI20[ ]+L1
-[ ]+14: R_LARCH_RELAX[ ]+\*ABS\*
-[ ]+18:[ ]+02c00084[ ]+addi.d[ ]+\$a0, \$a0, 0
-[ ]+18: R_LARCH_PCALA_LO12[ ]+L1
-[ ]+18: R_LARCH_RELAX[ ]+\*ABS\*
-[ ]+1c:[ ]+03400000[ ]+nop.*
-[ ]+1c: R_LARCH_ALIGN[ ]+.Lla-relax-align\+0x404
-[ ]+20:[ ]+03400000[ ]+nop.*
-[ ]+24:[ ]+03400000[ ]+nop.*
-[ ]+28:[ ]+1a000004[ ]+pcalau12i[ ]+\$a0, 0
-[ ]+28: R_LARCH_PCALA_HI20[ ]+L1
-[ ]+28: R_LARCH_RELAX[ ]+\*ABS\*
-[ ]+2c:[ ]+02c00084[ ]+addi.d[ ]+\$a0, \$a0, 0
-[ ]+2c: R_LARCH_PCALA_LO12[ ]+L1
-[ ]+2c: R_LARCH_RELAX[ ]+\*ABS\*
+[ ]+0:[ ]+4c000020[ ]+ret
+[ ]+4:[ ]+03400000[ ]+nop
+[ ]+4: R_LARCH_ALIGN[ ]+\*ABS\*\+0xc
+[ ]+8:[ ]+03400000[ ]+nop
+[ ]+c:[ ]+03400000[ ]+nop
+[ ]+10:[ ]+4c000020[ ]+ret
+[ ]+14:[ ]+03400000[ ]+nop
+[ ]+14: R_LARCH_ALIGN[ ]+\*ABS\*\+0xc
+[ ]+18:[ ]+03400000[ ]+nop
+[ ]+1c:[ ]+03400000[ ]+nop
+[ ]+20:[ ]+4c000020[ ]+ret
+[ ]+24:[ ]+03400000[ ]+nop
+[ ]+24: R_LARCH_ALIGN[ ]+.Lla-relax-align\+0x104
+[ ]+28:[ ]+03400000[ ]+nop
+[ ]+2c:[ ]+03400000[ ]+nop
+[ ]+30:[ ]+4c000020[ ]+ret
+[ ]+34:[ ]+03400000[ ]+nop
+[ ]+34: R_LARCH_ALIGN[ ]+.Lla-relax-align\+0xb04
+[ ]+38:[ ]+03400000[ ]+nop
+[ ]+3c:[ ]+03400000[ ]+nop
+[ ]+40:[ ]+4c000020[ ]+ret
+[ ]+44:[ ]+03400000[ ]+nop
+[ ]+44: R_LARCH_ALIGN[ ]+\*ABS\*\+0xc
+[ ]+48:[ ]+03400000[ ]+nop
+[ ]+4c:[ ]+03400000[ ]+nop
+[ ]+50:[ ]+4c000020[ ]+ret
+[ ]+54:[ ]+03400000[ ]+nop
+[ ]+54: R_LARCH_ALIGN[ ]+\*ABS\*\+0xc
+[ ]+58:[ ]+03400000[ ]+nop
+[ ]+5c:[ ]+03400000[ ]+nop
+[ ]+60:[ ]+4c000020[ ]+ret
+[ ]+64:[ ]+03400000[ ]+nop
+[ ]+64: R_LARCH_ALIGN[ ]+\*ABS\*\+0xc
+[ ]+68:[ ]+03400000[ ]+nop
+[ ]+6c:[ ]+03400000[ ]+nop
+[ ]+70:[ ]+4c000020[ ]+ret
diff --git a/gas/testsuite/gas/loongarch/relax_align.s b/gas/testsuite/gas/loongarch/relax_align.s
index c0177c88fc1..4f4867fb209 100644
--- a/gas/testsuite/gas/loongarch/relax_align.s
+++ b/gas/testsuite/gas/loongarch/relax_align.s
@@ -1,7 +1,19 @@
+# If max < -0x80000000, max becomes a positive number because type conversion
+# (bfd_signed_vma -> unsigned int).
.text
.L1:
- la.local $a0, L1
+ ret
.align 4
- la.local $a0, L1
- .align 4, , 4
- la.local $a0, L1
+ ret
+ .align 4, , 0
+ ret
+ .align 4, , 1
+ ret
+ .align 4, , 11
+ ret
+ .align 4, , 12
+ ret
+ .align 4, , -1
+ ret
+ .align 4, , -0x80000000
+ ret
--
2.36.0
reply other threads:[~2024-02-22 12:42 UTC|newest]
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