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| # REQUIRES: ppc
# RUN: llvm-mc -filetype=obj -triple=powerpc %s -o %t.o
# RUN: echo '.globl f, g, h; f: g: h:' | llvm-mc -filetype=obj -triple=powerpc - -o %t1.o
# RUN: ld.lld -shared %t1.o -soname t1.so -o %t1.so
# RUN: echo 'bl f+0x8000@plt' | llvm-mc -filetype=obj -triple=powerpc - -o %t2.o
## Check we can create PLT entries for -fPIE or -fpie executable.
# RUN: ld.lld -pie %t.o %t1.so %t2.o -o %t
# RUN: llvm-readobj -r %t | FileCheck --check-prefix=RELOC %s
# RUN: llvm-readobj -d %t | FileCheck --check-prefix=DYN %s
# RUN: llvm-readelf -S %t | FileCheck --check-prefix=SEC %s
# RUN: llvm-readelf -x .plt %t | FileCheck --check-prefix=HEX %s
# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck --check-prefixes=CHECK,PIE %s
## Check we can create PLT entries for -fPIC or -fpic DSO.
# RUN: ld.lld -shared %t.o %t1.so %t2.o -o %t
# RUN: llvm-readobj -r %t | FileCheck --check-prefix=RELOC %s
# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck --check-prefixes=CHECK,SHARED %s
# RELOC: .rela.dyn {
# RELOC-NEXT: R_PPC_ADDR32 f 0x0
# RELOC-NEXT: R_PPC_ADDR32 g 0x0
# RELOC-NEXT: R_PPC_ADDR32 h 0x0
# RELOC-NEXT: }
# RELOC-NEXT: .rela.plt {
# RELOC-NEXT: R_PPC_JMP_SLOT f 0x0
# RELOC-NEXT: R_PPC_JMP_SLOT g 0x0
# RELOC-NEXT: R_PPC_JMP_SLOT h 0x0
# RELOC-NEXT: }
# SEC: .got PROGBITS 00020374
# DYN: PPC_GOT 0x20374
## .got2+0x8000-0x10004 = 0x30000+0x8000-0x10004 = 65536*2+32764
# CHECK-LABEL: _start:
# CHECK-NEXT: bcl 20, 31, .+4
# PIE-NEXT: 10210: mflr 30
# PIE-NEXT: addis 30, 30, 3
# PIE-NEXT: addi 30, 30, -32400
# SHARED-NEXT: 10230: mflr 30
# SHARED-NEXT: addis 30, 30, 3
# SHARED-NEXT: addi 30, 30, -32408
## Two bl 00008000.got2.plt_pic32.f
# CHECK-NEXT: bl .+40
# CHECK-NEXT: bl .+36
## Two bl 00008000.got2.plt_pic32.g
# CHECK-NEXT: bl .+48
# CHECK-NEXT: bl .+44
## Two bl 00008000.got2.plt_pic32.h
# CHECK-NEXT: bl .+56
# CHECK-NEXT: bl .+52
# CHECK-NEXT: addis 30, 30, {{.*}}
# CHECK-NEXT: addi 30, 30, {{.*}}
## bl 00008000.plt_pic32.f
# CHECK-NEXT: bl .+56
## bl 00008000.plt_pic32.f
# CHECK-NEXT: bl .+68
# CHECK-EMPTY:
## -fPIC call stubs of f and g.
# CHECK-NEXT: 00008000.got2.plt_pic32.f:
# CHECK-NEXT: lwz 11, 32760(30)
# CHECK-NEXT: mtctr 11
# CHECK-NEXT: bctr
# CHECK-NEXT: nop
# CHECK-EMPTY:
# CHECK-NEXT: 00008000.got2.plt_pic32.g:
# CHECK-NEXT: lwz 11, 32764(30)
# CHECK-NEXT: mtctr 11
# CHECK-NEXT: bctr
# CHECK-NEXT: nop
# CHECK-EMPTY:
## The -fPIC call stub of h needs two instructions addis+lwz to represent the offset 65536*1-32768.
# CHECK-NEXT: 00008000.got2.plt_pic32.h:
# CHECK-NEXT: addis 11, 30, 1
# CHECK-NEXT: lwz 11, -32768(11)
# CHECK-NEXT: mtctr 11
# CHECK-NEXT: bctr
# CHECK-EMPTY:
## -fpic call stub of f.
# CHECK-NEXT: 00000000.plt_pic32.f:
# CHECK-NEXT: addis 11, 30, 2
# CHECK-NEXT: lwz 11, 4(11)
# CHECK-NEXT: mtctr 11
# CHECK-NEXT: bctr
# CHECK-EMPTY:
## Another -fPIC call stub of f from another object file %t2.o
## .got2 may have different addresses in different object files,
## so the call stub cannot be shared.
# CHECK-NEXT: 00008000.got2.plt_pic32.f:
## In Secure PLT ABI, .plt stores function pointers to first instructions of .glink
# HEX: 0x00040378 000102a0 000102a4 000102a8
## These instructions are referenced by .plt entries.
# PIE: 000102a0 .glink:
# SHARED: 000102c0 .glink:
# CHECK-NEXT: b .+12
# CHECK-NEXT: b .+8
# CHECK-NEXT: b .+4
## PLTresolve
## Operand of addi: 0x100a8-.glink = 24
# CHECK-NEXT: addis 11, 11, 0
# CHECK-NEXT: mflr 0
# CHECK-NEXT: bcl 20, 31, .+4
# PIE-NEXT: 102b8: addi 11, 11, 24
# SHARED-NEXT: 102d8: addi 11, 11, 24
# CHECK-NEXT: mflr 12
# CHECK-NEXT: mtlr 0
# CHECK-NEXT: subf 11, 12, 11
## Operand of lwz in -pie mode: &.got[1] - 0x100a8 = 0x20088+4 - 0x100a8 = 65536*1-28
# CHECK-NEXT: addis 12, 12, 1
# PIE-NEXT: lwz 0, 192(12)
# SHARED-NEXT: lwz 0, 184(12)
# PIE-NEXT: lwz 12, 196(12)
# SHARED-NEXT: lwz 12, 188(12)
# CHECK-NEXT: mtctr 0
# CHECK-NEXT: add 0, 11, 11
# CHECK-NEXT: add 11, 0, 11
# CHECK-NEXT: bctr
.section .got2,"aw"
.space 65516
.long f
.long g
.long h
.text
.globl _start
_start:
bcl 20,31,.L
.L:
mflr 30
addis 30, 30, .got2+0x8000-.L@ha
addi 30, 30, .got2+0x8000-.L@l
bl f+0x8000@plt
bl f+0x8000@plt
bl g+0x8000@plt
bl g+0x8000@plt
bl h+0x8000@plt
bl h+0x8000@plt
## An addend of 0 indicates r30 is stored in _GLOBAL_OFFSET_TABLE_.
## The existing thunk is incompatible, thus it cannot be reused.
addis 30, 30, _GLOBAL_OFFSET_TABLE_-.L@ha
addi 30, 30, _GLOBAL_OFFSET_TABLE_-.L@l
bl f@plt
|