Unverified Commit ec0ee3b5 authored by Fangrui Song's avatar Fangrui Song Committed by GitHub
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[SystemZ,test] Cover non-preemptible PLTOFF (#195600) 

R_390_PLTOFF{16,32,64} against a non-preemptible (hidden) symbol takes
fromPlt(R_PLT_GOTREL) → R_GOTREL in RelocScan::process so the relocation
resolves to symbol - .got with no PLT entry. Add tests to fix the
the test gap from the initial SystemZ port
(fe3406e3).
parent cd077bac

lld/test/ELF/systemz-reloc-gotrel.s

+31 −8
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 
# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o

# RUN: ld.lld -shared %t.o -soname=t.so -o %t.so



# RUN: llvm-readelf -S -s -x .data %t.so | FileCheck %s

# RUN: llvm-readelf -S -s -x .data -x .data1 %t.so | FileCheck %s



# CHECK: Section Headers:

# CHECK: .plt PROGBITS 0000000000001290
@@ -10,27 +10,50 @@ 


# CHECK: Symbol table '.symtab'

# CHECK: 0000000000001288 {{.*}}  bar

# CHECK: 000000000000128a {{.*}}  baz



## Note: foo is the first (and only) PLT entry, which resides at .plt + 32

## PLTOFF (foo) is (.plt + 32) - .got == 0x12b0 - 0x2390 == 0xffffef20

## GOTOFF (bar) is bar - .got == 0x1288 - 0x2390 == 0xffffeef8

## .data holds relocations against non-preemptible symbols (link-time

## constants): GOTOFF (bar) and PLTOFF (baz). For PLTOFF (baz) the scan

## rewrites R_PLT_GOTREL → R_GOTREL via fromPlt so the result is

## baz - .got, not the offset of a PLT entry.

## GOTOFF (bar) = bar - .got = 0x1288 - 0x2390 = 0xffffeef8

## PLTOFF (baz) = baz - .got = 0x128a - 0x2390 = 0xffffeefa

# CHECK: Hex dump of section '.data':

# CHECK-NEXT: eef8ef20 ffffeef8 ffffef20 ffffffff

# CHECK-NEXT: ffffeef8 ffffffff ffffef20

# CHECK-NEXT: eef8eefa ffffeef8 ffffeefa ffffffff

# CHECK-NEXT: ffffeef8 ffffffff ffffeefa



## .data1 holds relocations against the preemptible foo, which uses the

## first (and only) PLT entry at .plt + 32.

## PLTOFF (foo) = (.plt + 32) - .got = 0x12b0 - 0x2390 = 0xffffef20

# CHECK: Hex dump of section '.data1':

# CHECK-NEXT: ef20ffff ef20ffff ffffffff ef20



bar:

  br %r14



.hidden baz

.globl baz

baz:

  br %r14



.data

.reloc ., R_390_GOTOFF16, bar

.space 2

.reloc ., R_390_PLTOFF16, foo

.reloc ., R_390_PLTOFF16, baz

.space 2

.reloc ., R_390_GOTOFF, bar

.space 4

.reloc ., R_390_PLTOFF32, foo

.reloc ., R_390_PLTOFF32, baz

.space 4

.reloc ., R_390_GOTOFF64, bar

.space 8

.reloc ., R_390_PLTOFF64, baz

.space 8



.section .data1,"aw"

.reloc ., R_390_PLTOFF16, foo

.space 2

.reloc ., R_390_PLTOFF32, foo

.space 4

.reloc ., R_390_PLTOFF64, foo

.space 8