Index: ELF/Arch/RISCV.cpp
===================================================================
--- ELF/Arch/RISCV.cpp
+++ ELF/Arch/RISCV.cpp
@@ -42,10 +42,21 @@
template <class ELFT>
class RISCV final : public TargetInfo {
public:
- RISCV() {}
+ RISCV();
RelExpr getRelExpr(uint32_t Type, const SymbolBody &S,
const uint8_t *Loc) const override;
void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override;
+
+ virtual void writeGotPltHeader(uint8_t *Buf) const override;
+ virtual void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override;
+
+ virtual void writePltHeader(uint8_t *Buf) const override;
+
+ virtual void writePlt(uint8_t *Buf, uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const override;
+
+ virtual bool usesOnlyLowPageBits(uint32_t Type) const override;
};
// RISC-V instructions are stored as 16-bit parcels starting with lower bits;
@@ -61,6 +72,98 @@
return read16<E>(Buf) | static_cast<uint32_t>(read16<E>(Buf + 2)) << 16;
}
+template <class ELFT>
+RISCV<ELFT>::RISCV()
+{
+ CopyRel = R_RISCV_COPY;
+ RelativeRel = R_RISCV_RELATIVE;
+ GotRel = ELFT::Is64Bits ? R_RISCV_64 : R_RISCV_32;
+ PltRel = R_RISCV_JUMP_SLOT;
+ GotEntrySize = sizeof(typename ELFT::uint);
+ GotPltEntrySize = sizeof(typename ELFT::uint);
+ PltEntrySize = 16;
+ PltHeaderSize = 32;
+ GotPltHeaderEntriesNum = 2;
+}
+
+template <class ELFT>
+bool RISCV<ELFT>::usesOnlyLowPageBits(uint32_t Type) const {
+ return Type == R_RISCV_LO12_I || Type == R_RISCV_PCREL_LO12_I
+ || Type == R_RISCV_LO12_S || Type == R_RISCV_PCREL_LO12_S
+ // These are used in a pair to calculate relative address in debug
+ // sections, so they aren't really absolute. We list those here as a hack
+ // so the linker doesn't try to create dynamic relocations.
+ || Type == R_RISCV_ADD8 || Type == R_RISCV_ADD16
+ || Type == R_RISCV_ADD32 || Type == R_RISCV_ADD64
+ || Type == R_RISCV_SUB8 || Type == R_RISCV_SUB16
+ || Type == R_RISCV_SUB32 || Type == R_RISCV_SUB64
+ || Type == R_RISCV_SUB6
+ || Type == R_RISCV_SET6 || Type == R_RISCV_SET8
+ || Type == R_RISCV_SET16 || Type == R_RISCV_SET32;
+}
+
+template <class ELFT>
+void RISCV<ELFT>::writeGotPltHeader(uint8_t *Buf) const {
+ constexpr endianness E = ELFT::TargetEndianness;
+ using uint = typename ELFT::uint;
+
+ write<uint, E>(Buf, -1);
+ write<uint, E>(Buf + 1 * sizeof(uint), 0);
+}
+
+template <class ELFT>
+void RISCV<ELFT>::writeGotPlt(uint8_t *Buf, const SymbolBody &S) const {
+ write<typename ELFT::uint, ELFT::TargetEndianness>(Buf, InX::Plt->getVA());
+}
+
+template <class ELFT>
+void RISCV<ELFT>::writePltHeader(uint8_t *Buf) const
+{
+ constexpr endianness E = ELFT::TargetEndianness;
+ const uint64_t PcRelGotPlt = InX::GotPlt->getVA() - InX::Plt->getVA();
+
+ writeInsn32<E>(Buf + 0, 0x00000397); // 1: auipc t2, %pcrel_hi(.got.plt)
+ relocateOne(Buf + 0, R_RISCV_PCREL_HI20, PcRelGotPlt);
+ writeInsn32<E>(Buf + 4, 0x41c30333); // sub t1, t1, t3
+ if (ELFT::Is64Bits) {
+ writeInsn32<E>(Buf + 8, 0x0003be03); // ld t3, %pcrel_lo(1b)(t2)
+ } else {
+ writeInsn32<E>(Buf + 8, 0x0003ae03); // lw t3, %pcrel_lo(1b)(t2)
+ }
+ relocateOne(Buf + 8, R_RISCV_PCREL_LO12_I, PcRelGotPlt);
+ writeInsn32<E>(Buf + 12, 0xfd430313); // addi t1, t1, -44
+ writeInsn32<E>(Buf + 16, 0x00038293); // addi t0, t2, %pcrel_lo(1b)
+ relocateOne(Buf + 16, R_RISCV_PCREL_LO12_I, PcRelGotPlt);
+ if (ELFT::Is64Bits) {
+ writeInsn32<E>(Buf + 20, 0x00135313); // srli t1, t1, 1
+ writeInsn32<E>(Buf + 24, 0x0082b283); // ld t0, 8(t0)
+ } else {
+ writeInsn32<E>(Buf + 20, 0x00235313); // srli t1, t1, 2
+ writeInsn32<E>(Buf + 24, 0x0042a283); // lw t0, 4(t0)
+ }
+ writeInsn32<E>(Buf + 28, 0x000e0067); // jr t3
+}
+
+template <class ELFT>
+void RISCV<ELFT>::writePlt(uint8_t *Buf, uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const
+{
+ constexpr endianness E = ELFT::TargetEndianness;
+
+ writeInsn32<E>(Buf + 0, 0x00000e17); // auipc t3, %pcrel_hi(f@.got.plt)
+ if (ELFT::Is64Bits) {
+ writeInsn32<E>(Buf + 4, 0x000e3e03); // ld t3, %pcrel_lo(-4)(t3)
+ } else {
+ writeInsn32<E>(Buf + 4, 0x000e2e03); // lw t3, %pcrel_lo(-4)(t3)
+ }
+ writeInsn32<E>(Buf + 8, 0x000e0367); // jalr t1, t3
+ writeInsn32<E>(Buf + 12, 0x00000013); // nop
+
+ relocateOne(Buf + 0, R_RISCV_PCREL_HI20, GotEntryAddr - PltEntryAddr);
+ relocateOne(Buf + 4, R_RISCV_PCREL_LO12_I, GotEntryAddr - PltEntryAddr);
+}
+
template <class ELFT>
RelExpr RISCV<ELFT>::getRelExpr(const uint32_t Type, const SymbolBody &S,
const uint8_t *Loc) const {
@@ -73,11 +176,15 @@
case R_RISCV_RVC_JUMP:
case R_RISCV_32_PCREL:
return R_PC;
+ case R_RISCV_CALL_PLT:
+ return R_PLT_PC;
case R_RISCV_PCREL_LO12_I:
case R_RISCV_PCREL_LO12_S:
return R_RISCV_PC_INDIRECT;
- case R_RISCV_RELAX:
+ case R_RISCV_GOT_HI20:
+ return R_GOT_PC;
case R_RISCV_ALIGN:
+ case R_RISCV_RELAX:
return R_HINT;
default:
return R_ABS;
@@ -178,6 +285,7 @@
return;
}
// auipc + jalr pair
+ case R_RISCV_CALL_PLT:
case R_RISCV_CALL: {
checkInt<32>(Loc, static_cast<int64_t>(Val), Type);
const uint32_t Hi = Val + 0x800;
@@ -189,6 +297,7 @@
}
case R_RISCV_PCREL_HI20:
+ case R_RISCV_GOT_HI20:
case R_RISCV_HI20: {
checkInt<32>(Loc, static_cast<int64_t>(Val), Type);
const uint32_t Hi = Val + 0x800;
Index: ELF/InputSection.cpp
===================================================================
--- ELF/InputSection.cpp
+++ ELF/InputSection.cpp
@@ -576,7 +576,7 @@
for (const Relocation& HiRel: IS->Relocations) {
const uint64_t HiOffset = IS->getOffset(HiRel.Offset);
const uint64_t HiAddrLoc = IS->getOutputSection()->Addr + HiOffset;
- if (Label == HiAddrLoc && isRelExprOneOf<R_PC>(HiRel.Expr)) {
+ if (Label == HiAddrLoc && isRelExprOneOf<R_PC, R_PLT_PC, R_GOT_PC>(HiRel.Expr)) {
return getRelocTargetVA(
HiRel.Type, HiRel.Addend, HiAddrLoc, *HiRel.Sym, HiRel.Expr);
}
Index: ELF/Relocations.cpp
===================================================================
--- ELF/Relocations.cpp
+++ ELF/Relocations.cpp
@@ -356,7 +356,7 @@
// file (PC, or GOT for example).
static bool isRelExpr(RelExpr Expr) {
return isRelExprOneOf<R_PC, R_GOTREL, R_GOTREL_FROM_END, R_MIPS_GOTREL,
- R_PAGE_PC, R_RELAX_GOT_PC>(Expr);
+ R_PAGE_PC, R_RELAX_GOT_PC, R_RISCV_PC_INDIRECT>(Expr);
}
// Returns true if a given relocation can be computed at link-time.
@@ -413,6 +413,11 @@
if (Body.isUndefWeak())
return true;
+ // __global_pointer$ is defined as absolute but will be set to .sdata + 0x800
+ // by Writer during finalization, so we white-list it here.
+ if (Config->Pie && &Body == ElfSym::RISCVGlobalPointer)
+ return true;
+
error("relocation " + toString(Type) + " cannot refer to absolute symbol: " +
toString(Body) + getLocation<ELFT>(S, Body, RelOff));
return true;
Index: test/ELF/Inputs/riscv-shared.yaml
===================================================================
--- /dev/null
+++ test/ELF/Inputs/riscv-shared.yaml
@@ -0,0 +1,42 @@
+--- !ELF
+FileHeader:
+ Class: ELFCLASS32
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_RISCV
+ Flags: [ EF_RISCV_RVC, EF_RISCV_FLOAT_ABI_SOFT ]
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ AddressAlign: 0x0000000000000002
+ Content: ''
+ - Name: .data
+ Type: SHT_PROGBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+ Content: 2A000000
+ - Name: .bss
+ Type: SHT_NOBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+Symbols:
+ Local:
+ - Name: .text
+ Type: STT_SECTION
+ Section: .text
+ - Name: .data
+ Type: STT_SECTION
+ Section: .data
+ - Name: .bss
+ Type: STT_SECTION
+ Section: .bss
+ Global:
+ - Name: f
+ Type: STT_FUNC
+ Section: .text
+ - Name: x
+ Type: STT_OBJECT
+ Section: .data
+ Size: 0x0000000000000004
+...
Index: test/ELF/riscv-copy.test
===================================================================
--- /dev/null
+++ test/ELF/riscv-copy.test
@@ -0,0 +1,78 @@
+# .option norelax
+# .global _start
+#
+# .section .text, "ax", @progbits
+# _start:
+# la a0, x
+#
+# REQUIRES: riscv
+# RUN: yaml2obj %s -o %t.o
+# RUN: yaml2obj %p/Inputs/riscv-shared.yaml -o %t2.o
+# RUN: ld.lld -shared %t2.o -o %t3.so
+# RUN: ld.lld %t.o %t3.so -o %t -Tbss=0x13000 -Ttext=0x10000
+# RUN: llvm-readelf -r %t | FileCheck -check-prefix=READELF %s
+# RUN: obj2yaml %t | FileCheck %s
+#
+# READELF: Relocation section '.rela.dyn'
+# READELF: 00013000 00000104 R_RISCV_COPY 00013000 x + 0
+#
+# CHECK: - Name: .text
+# CHECK: Content: '1735000013050500'
+# CHECK: - Name: .bss
+#
+# 10000: 00003517 auipc a0,0x3
+# 10004: 00050513 mv a0,a0
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS32
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_RISCV
+ Flags: [ EF_RISCV_RVC, EF_RISCV_FLOAT_ABI_SOFT ]
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ AddressAlign: 0x0000000000000002
+ Content: '1705000013050500'
+ - Name: .rela.text
+ Type: SHT_RELA
+ Flags: [ SHF_INFO_LINK ]
+ Link: .symtab
+ AddressAlign: 0x0000000000000004
+ Info: .text
+ Relocations:
+ - Offset: 0x0000000000000000
+ Symbol: x
+ Type: R_RISCV_PCREL_HI20
+ - Offset: 0x0000000000000004
+ Symbol: '.L0 '
+ Type: R_RISCV_PCREL_LO12_I
+ - Name: .data
+ Type: SHT_PROGBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+ Content: ''
+ - Name: .bss
+ Type: SHT_NOBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+Symbols:
+ Local:
+ - Name: .text
+ Type: STT_SECTION
+ Section: .text
+ - Name: .data
+ Type: STT_SECTION
+ Section: .data
+ - Name: .bss
+ Type: STT_SECTION
+ Section: .bss
+ - Name: '.L0 '
+ Section: .text
+ Global:
+ - Name: _start
+ Section: .text
+ - Name: x
+...
Index: test/ELF/riscv-fpic-got.test
===================================================================
--- /dev/null
+++ test/ELF/riscv-fpic-got.test
@@ -0,0 +1,80 @@
+# .option norelax
+# .option pic
+# .global _start
+#
+# .section .text, "ax", @progbits
+# _start:
+# la a0, x
+#
+# REQUIRES: riscv
+# RUN: yaml2obj %s -o %t.o
+# RUN: yaml2obj %p/Inputs/riscv-shared.yaml -o %t2.o
+# RUN: ld.lld -shared %t2.o -o %t3.so
+# RUN: ld.lld %t.o %t3.so -o %t --section-start .got=0x20000 --section-start .text=0x10000
+# RUN: llvm-readelf -r %t | FileCheck -check-prefix=READELF %s
+# RUN: obj2yaml %t | FileCheck %s
+#
+# READELF: Relocation section '.rela.dyn'
+# READELF: 00020000 00000101 R_RISCV_32 00000000 x + 0
+#
+# CHECK: - Name: .text
+# CHECK: Content: '1705010003250500'
+#
+# 10000: 00010517 auipc a0,0x10
+# 10004: 00052503 lw a0,0(a0) # 20000 <_start+0x10000>
+#
+# CHECK: - Name: .got
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS32
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_RISCV
+ Flags: [ EF_RISCV_RVC, EF_RISCV_FLOAT_ABI_SOFT ]
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ AddressAlign: 0x0000000000000002
+ Content: '1705000003250500'
+ - Name: .rela.text
+ Type: SHT_RELA
+ Flags: [ SHF_INFO_LINK ]
+ Link: .symtab
+ AddressAlign: 0x0000000000000004
+ Info: .text
+ Relocations:
+ - Offset: 0x0000000000000000
+ Symbol: x
+ Type: R_RISCV_GOT_HI20
+ - Offset: 0x0000000000000004
+ Symbol: '.L0 '
+ Type: R_RISCV_PCREL_LO12_I
+ - Name: .data
+ Type: SHT_PROGBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+ Content: ''
+ - Name: .bss
+ Type: SHT_NOBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+Symbols:
+ Local:
+ - Name: .text
+ Type: STT_SECTION
+ Section: .text
+ - Name: .data
+ Type: STT_SECTION
+ Section: .data
+ - Name: .bss
+ Type: STT_SECTION
+ Section: .bss
+ - Name: '.L0 '
+ Section: .text
+ Global:
+ - Name: _start
+ Section: .text
+ - Name: x
+...
Index: test/ELF/riscv-fpic-pie.test
===================================================================
--- /dev/null
+++ test/ELF/riscv-fpic-pie.test
@@ -0,0 +1,77 @@
+# .option norelax
+# .option pic
+# .global _start
+#
+# .section .text, "ax", @progbits
+# _start:
+# la a0, _start
+#
+# REQUIRES: riscv
+# RUN: yaml2obj %s -o %t.o
+# RUN: ld.lld %t.o -o %t -pie --section-start .got=0x20000 --section-start .text=0x10000
+# RUN: llvm-readelf -r %t | FileCheck -check-prefix=READELF %s
+# RUN: obj2yaml %t | FileCheck %s
+#
+# READELF: Relocation section '.rela.dyn'
+# READELF: 00020000 00000003 R_RISCV_RELATIVE 10000
+#
+# CHECK: - Name: .text
+# CHECK: Content: '1705010003250500'
+#
+# 10000: 00010517 auipc a0,0x10
+# 10004: 00052503 lw a0,0(a0) # 20000 <_start+0x10000>
+#
+# CHECK: - Name: .got
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS32
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_RISCV
+ Flags: [ EF_RISCV_RVC, EF_RISCV_FLOAT_ABI_SOFT ]
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ AddressAlign: 0x0000000000000002
+ Content: '1705000003250500'
+ - Name: .rela.text
+ Type: SHT_RELA
+ Flags: [ SHF_INFO_LINK ]
+ Link: .symtab
+ AddressAlign: 0x0000000000000004
+ Info: .text
+ Relocations:
+ - Offset: 0x0000000000000000
+ Symbol: _start
+ Type: R_RISCV_GOT_HI20
+ - Offset: 0x0000000000000004
+ Symbol: '.L0 '
+ Type: R_RISCV_PCREL_LO12_I
+ - Name: .data
+ Type: SHT_PROGBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+ Content: ''
+ - Name: .bss
+ Type: SHT_NOBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+Symbols:
+ Local:
+ - Name: .text
+ Type: STT_SECTION
+ Section: .text
+ - Name: .data
+ Type: STT_SECTION
+ Section: .data
+ - Name: .bss
+ Type: STT_SECTION
+ Section: .bss
+ - Name: '.L0 '
+ Section: .text
+ Global:
+ - Name: _start
+ Section: .text
+...
Index: test/ELF/riscv-fpic-plt.test
===================================================================
--- /dev/null
+++ test/ELF/riscv-fpic-plt.test
@@ -0,0 +1,86 @@
+# .option norelax
+# .option pic
+# .global _start
+#
+# .section .text, "ax", @progbits
+# _start:
+# call f@plt
+#
+# REQUIRES: riscv
+# RUN: yaml2obj %s -o %t.o
+# RUN: yaml2obj %p/Inputs/riscv-shared.yaml -o %t2.o
+# RUN: ld.lld -shared %t2.o -o %t3.so
+# RUN: ld.lld %t.o %t3.so -o %t --section-start .text=0x10000 --section-start .got.plt=0x20000 --section-start .plt=0x21000
+# RUN: llvm-readelf -r %t | FileCheck -check-prefix=READELF %s
+# RUN: obj2yaml %t | FileCheck %s
+#
+# READELF: Relocation section '.rela.plt'
+# READELF: 00020008 00000105 R_RISCV_JUMP_SLOT 00000000 f + 0
+#
+# CHECK: - Name: .text
+# CHECK: Content: '97100100E7800002'
+# 10000: 00011097 auipc ra,0x11
+# 10004: 020080e7 jalr 32(ra) # 21020 <f@plt>
+#
+# CHECK: - Name: .got.plt
+# CHECK: Content: FFFFFFFF0000000000100200
+#
+# CHECK: - Name: .plt
+# CHECK: Content: 97F3FFFF3303C34103AE0300130343FD938203001353230083A2420067000E0017FEFFFF032E8EFE67030E0013000000
+# 21000: fffff397 auipc t2,0xfffff
+# 21004: 41c30333 sub t1,t1,t3
+# 21008: 0003ae03 lw t3,0(t2) # 20000 <_start+0x10000>
+# 2100c: fd430313 addi t1,t1,-44
+# 21010: 00038293 mv t0,t2
+# 21014: 00235313 srli t1,t1,0x2
+# 21018: 0042a283 lw t0,4(t0)
+# 2101c: 000e0067 jr t3
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS32
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_RISCV
+ Flags: [ EF_RISCV_RVC, EF_RISCV_FLOAT_ABI_SOFT ]
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ AddressAlign: 0x0000000000000002
+ Content: '97000000E7800000'
+ - Name: .rela.text
+ Type: SHT_RELA
+ Flags: [ SHF_INFO_LINK ]
+ Link: .symtab
+ AddressAlign: 0x0000000000000004
+ Info: .text
+ Relocations:
+ - Offset: 0x0000000000000000
+ Symbol: f
+ Type: R_RISCV_CALL_PLT
+ - Name: .data
+ Type: SHT_PROGBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+ Content: ''
+ - Name: .bss
+ Type: SHT_NOBITS
+ Flags: [ SHF_WRITE, SHF_ALLOC ]
+ AddressAlign: 0x0000000000000001
+Symbols:
+ Local:
+ - Name: .text
+ Type: STT_SECTION
+ Section: .text
+ - Name: .data
+ Type: STT_SECTION
+ Section: .data
+ - Name: .bss
+ Type: STT_SECTION
+ Section: .bss
+ Global:
+ - Name: _start
+ Section: .text
+ - Name: f
+...