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[lld][ELF] Combine uniqued small data sections #104485

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Merged
merged 1 commit into from
Aug 19, 2024
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[lld][ELF] Combine uniqued small data sections #104485

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11 changes: 7 additions & 4 deletions lld/ELF/LinkerScript.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -106,10 +106,13 @@ static StringRef getOutputSectionName(const InputSectionBase *s) {
return ".text";
}

for (StringRef v :
{".data.rel.ro", ".data", ".rodata", ".bss.rel.ro", ".bss", ".ldata",
".lrodata", ".lbss", ".gcc_except_table", ".init_array", ".fini_array",
".tbss", ".tdata", ".ARM.exidx", ".ARM.extab", ".ctors", ".dtors"})
for (StringRef v : {".data.rel.ro", ".data", ".rodata",
".bss.rel.ro", ".bss", ".ldata",
".lrodata", ".lbss", ".gcc_except_table",
".init_array", ".fini_array", ".tbss",
".tdata", ".ARM.exidx", ".ARM.extab",
".ctors", ".dtors", ".sbss",
".sdata", ".srodata"})
if (isSectionPrefix(v, s->name))
return v;

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34 changes: 21 additions & 13 deletions lld/test/ELF/riscv-section-layout.s
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Expand Up @@ -15,12 +15,13 @@
# RUN: ld.lld -pie %t.64s.o -o %t.64s
# RUN: llvm-readelf -S -sX %t.64s | FileCheck %s

# NOSDATA: .text
# NOSDATA: .rodata PROGBITS
# NOSDATA-NEXT: .text PROGBITS
# NOSDATA-NEXT: .tdata PROGBITS [[#%x,TDATA:]]
# NOSDATA-NEXT: .tbss
# NOSDATA-NEXT: .dynamic
# NOSDATA-NEXT: .got
# NOSDATA-NEXT: .relro_padding
# NOSDATA-NEXT: .tbss NOBITS
# NOSDATA-NEXT: .dynamic DYNAMIC
# NOSDATA-NEXT: .got PROGBITS
# NOSDATA-NEXT: .relro_padding NOBITS
# NOSDATA-NEXT: .data PROGBITS [[#%x,DATA:]]
# NOSDATA-NEXT: .bss NOBITS [[#%x,BSS:]]

Expand All @@ -33,16 +34,18 @@
# NOSDATA-DAG: [[#]]: {{0*}}[[#BSS]] 0 NOTYPE GLOBAL DEFAULT [[#]] (.bss) __bss_start
# NOSDATA-DAG: [[#]]: {{0*}}800 0 NOTYPE GLOBAL DEFAULT 1 (.dynsym) __global_pointer$

# CHECK: .text
# CHECK-NEXT: .tdata
# CHECK-NEXT: .tbss
# CHECK-NEXT: .dynamic
# CHECK-NEXT: .got
# CHECK-NEXT: .relro_padding
# CHECK-NEXT: .data
# CHECK: .rodata PROGBITS
# CHECK-NEXT: .srodata PROGBITS
# CHECK-NEXT: .text PROGBITS
# CHECK-NEXT: .tdata PROGBITS
# CHECK-NEXT: .tbss NOBITS
# CHECK-NEXT: .dynamic DYNAMIC
# CHECK-NEXT: .got PROGBITS
# CHECK-NEXT: .relro_padding NOBITS
# CHECK-NEXT: .data PROGBITS
# CHECK-NEXT: .sdata PROGBITS [[#%x,SDATA:]]
# CHECK-NEXT: .sbss NOBITS [[#%x,SBSS:]]
# CHECK-NEXT: .bss
# CHECK-NEXT: .bss NOBITS

# CHECK-DAG: [[#]]: {{0*}}[[#SBSS]] 0 NOTYPE GLOBAL DEFAULT [[#]] (.sdata) _edata
# CHECK-DAG: [[#]]: {{0*}}[[#SBSS]] 0 NOTYPE GLOBAL DEFAULT [[#]] (.sbss) __bss_start
Expand All @@ -51,11 +54,16 @@
.globl _etext, _edata, __bss_start
lla gp, __global_pointer$

.section .rodata,"a",@progbits; .space 1
.section .data,"aw",@progbits; .long _GLOBAL_OFFSET_TABLE_ - .
.section .bss,"aw",@nobits; .space 1
.section .tdata,"awT",@progbits; .space 1
.section .tbss,"awT",@nobits; .space 1
.ifdef SDATA
.section .sdata,"aw",@progbits; .space 1
.section .sdata.suffix,"aw",@progbits; .space 1
.section .sbss,"aw",@nobits; .space 1
.section .sbss.suffix,"aw",@nobits; .space 1
.section .srodata,"a",@progbits; .space 1
.section .srodata.suffix,"a",@progbits; .space 1
.endif
19 changes: 17 additions & 2 deletions lld/test/ELF/section-name.s
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Expand Up @@ -41,19 +41,34 @@ _start:
.byte 0
.section .tdata.foo,"aGwT",@progbits,foo,comdat
.byte 0
.section .sdata,"aw"
.byte 0
.section .sdata.foo,"aw"
.byte 0
.section .sbss,"aw",@nobits
.byte 0
.section .sbss.foo,"aw",@nobits
.byte 0
.section .srodata,"a"
.byte 0
.section .srodata.foo,"a"
.byte 0

// CHECK: .rodata 00000002
// CHECK-NEXT: .gcc_except_table 00000001
// CHECK-NEXT: .srodata 00000002
// CHECK-NEXT: .text 00000002
// CHECK-NEXT: .tdata 00000001
// CHECK-NEXT: .tbss 00000001
// CHECK-NEXT: .data.rel.ro 00000004
// CHECK-NEXT: .relro_padding 00000df5
// CHECK-NEXT: .relro_padding 00000df1
// CHECK-NEXT: .data 00000002
// CHECK-NEXT: .foo.a 00000001
// CHECK-NEXT: .foo 00000001
// CHECK-NEXT: .sdata 00000002
// CHECK-NEXT: .bss 00000002
// CHECK-NEXT: .sbss 00000002
// CHECK-NEXT: .comment 00000008
// CHECK-NEXT: .symtab 00000030
// CHECK-NEXT: .shstrtab 00000084
// CHECK-NEXT: .shstrtab 0000009a
// CHECK-NEXT: .strtab 00000008
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