[ARM] Implement relocations: R_ARM_REL32, R_ARM_THM_JUMP11, R_ARM_PREL31

Test case for every relocation is added. Differential Revision: http://reviews.llvm.org/D7565 llvm-svn: 232464
llvm · Mar 17, 2015 · e458ab4 · e458ab4
1 parent b326765
commit e458ab4
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Showing 4 changed files with 367 additions and 1 deletion.
diff --git a/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationHandler.cpp b/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationHandler.cpp
@@ -70,6 +70,13 @@ static Reference::Addend readAddend_ARM_CALL(const uint8_t *location) {
   return llvm::SignExtend64<26>(result);
 }
 
+static Reference::Addend readAddend_THM_JUMP11(const uint8_t *location) {
+  const auto value = read16le(location);
+  const uint16_t imm11 = value & 0x7FF;
+
+  return llvm::SignExtend32<12>(imm11 << 1);
+}
+
 static Reference::Addend readAddend(const uint8_t *location,
                                     Reference::KindValue kindValue) {
   switch (kindValue) {
@@ -78,6 +85,8 @@ static Reference::Addend readAddend(const uint8_t *location,
   case R_ARM_THM_CALL:
   case R_ARM_THM_JUMP24:
     return readAddend_THM_CALL(location);
+  case R_ARM_THM_JUMP11:
+    return readAddend_THM_JUMP11(location);
   case R_ARM_CALL:
   case R_ARM_JUMP24:
     return readAddend_ARM_CALL(location);
@@ -107,6 +116,12 @@ static inline void applyThmReloc(uint8_t *location, uint16_t resHi,
   write16le(location, (read16le(location) & ~maskLo) | (resLo & maskLo));
 }
 
+static inline void applyThumb16Reloc(uint8_t *location, uint16_t result,
+                                     uint16_t mask = 0xFFFF) {
+  assert(!(result & ~mask));
+  write16le(location, (read16le(location) & ~mask) | (result & mask));
+}
+
 /// \brief R_ARM_ABS32 - (S + A) | T
 static void relocR_ARM_ABS32(uint8_t *location, uint64_t P, uint64_t S,
                              int64_t A, bool addressesThumb) {
@@ -123,6 +138,42 @@ static void relocR_ARM_ABS32(uint8_t *location, uint64_t P, uint64_t S,
   applyArmReloc(location, result);
 }
 
+/// \brief R_ARM_REL32 - ((S + A) | T) - P
+static void relocR_ARM_REL32(uint8_t *location, uint64_t P, uint64_t S,
+                             int64_t A, bool addressesThumb) {
+  uint64_t T = addressesThumb;
+  uint32_t result = (uint32_t)(((S + A) | T) - P);
+
+  DEBUG_WITH_TYPE(
+      "ARM", llvm::dbgs() << "\t\tHandle " << LLVM_FUNCTION_NAME << " -";
+      llvm::dbgs() << " S: 0x" << Twine::utohexstr(S);
+      llvm::dbgs() << " A: 0x" << Twine::utohexstr(A);
+      llvm::dbgs() << " P: 0x" << Twine::utohexstr(P);
+      llvm::dbgs() << " T: 0x" << Twine::utohexstr(T);
+      llvm::dbgs() << " result: 0x" << Twine::utohexstr(result) << "\n");
+  applyArmReloc(location, result);
+}
+
+/// \brief R_ARM_PREL31 - ((S + A) | T) - P
+static void relocR_ARM_PREL31(uint8_t *location, uint64_t P, uint64_t S,
+                                  int64_t A, bool addressesThumb) {
+  uint64_t T = addressesThumb;
+  uint32_t result = (uint32_t)(((S + A) | T) - P);
+  const uint32_t mask = 0x7FFFFFFF;
+  uint32_t rel31 = result & mask;
+
+  DEBUG_WITH_TYPE(
+      "ARM", llvm::dbgs() << "\t\tHandle " << LLVM_FUNCTION_NAME << " -";
+      llvm::dbgs() << " S: 0x" << Twine::utohexstr(S);
+      llvm::dbgs() << " A: 0x" << Twine::utohexstr(A);
+      llvm::dbgs() << " P: 0x" << Twine::utohexstr(P);
+      llvm::dbgs() << " T: 0x" << Twine::utohexstr(T);
+      llvm::dbgs() << " result: 0x" << Twine::utohexstr(result);
+      llvm::dbgs() << " rel31: 0x" << Twine::utohexstr(rel31) << "\n");
+
+  applyArmReloc(location, rel31, mask);
+}
+
 /// \brief Relocate B/BL instructions. useJs defines whether J1 & J2 are used
 static void relocR_ARM_THM_B_L(uint8_t *location, uint32_t result, bool useJs) {
   result = (result & 0x01FFFFFE) >> 1;
@@ -183,6 +234,24 @@ static void relocR_ARM_THM_JUMP24(uint8_t *location, uint64_t P, uint64_t S,
   relocR_ARM_THM_B_L(location, result, true);
 }
 
+/// \brief R_ARM_THM_JUMP11 - S + A - P
+static void relocR_ARM_THM_JUMP11(uint8_t *location, uint64_t P, uint64_t S,
+                                  int64_t A) {
+  uint32_t result = (uint32_t)(S + A - P);
+
+  DEBUG_WITH_TYPE(
+      "ARM", llvm::dbgs() << "\t\tHandle " << LLVM_FUNCTION_NAME << " -";
+      llvm::dbgs() << " S: 0x" << Twine::utohexstr(S);
+      llvm::dbgs() << " A: 0x" << Twine::utohexstr(A);
+      llvm::dbgs() << " P: 0x" << Twine::utohexstr(P);
+      llvm::dbgs() << " result: 0x" << Twine::utohexstr(result) << "\n");
+
+  //we cut off first bit because it is always 1 according to p. 4.5.3
+  result = (result & 0x0FFE) >> 1;
+
+  applyThumb16Reloc(location, result, 0x7FF);
+}
+
 /// \brief R_ARM_CALL - ((S + A) | T) - P
 static void relocR_ARM_CALL(uint8_t *location, uint64_t P, uint64_t S,
                             int64_t A, bool addressesThumb) {
@@ -274,7 +343,7 @@ static void relocR_ARM_THM_MOV(uint8_t *location, uint32_t result) {
   const uint16_t bitI = (result >> 11) & 0x1;
   const uint16_t resHi = (bitI << 10) | imm4;
 
- applyThmReloc(location, resHi, resLo, 0x40F, 0x70FF);
+  applyThmReloc(location, resHi, resLo, 0x40F, 0x70FF);
 }
 
 /// \brief R_ARM_THM_MOVW_ABS_NC - (S + A) | T
@@ -340,6 +409,10 @@ std::error_code ARMTargetRelocationHandler::applyRelocation(
     relocR_ARM_ABS32(location, relocVAddress, targetVAddress, addend,
                      addressesThumb);
     break;
+  case R_ARM_REL32:
+    relocR_ARM_REL32(location, relocVAddress, targetVAddress, addend,
+                     addressesThumb);
+    break;
   case R_ARM_THM_CALL:
     // TODO: consider adding bool variable to disable J1 & J2 for archs
     // before ARMv6
@@ -358,6 +431,9 @@ std::error_code ARMTargetRelocationHandler::applyRelocation(
     relocR_ARM_THM_JUMP24(location, relocVAddress, targetVAddress, addend,
                           addressesThumb);
     break;
+  case R_ARM_THM_JUMP11:
+    relocR_ARM_THM_JUMP11(location, relocVAddress, targetVAddress, addend);
+    break;
   case R_ARM_MOVW_ABS_NC:
     relocR_ARM_MOVW_ABS_NC(location, relocVAddress, targetVAddress, addend,
                            addressesThumb);
@@ -372,6 +448,10 @@ std::error_code ARMTargetRelocationHandler::applyRelocation(
   case R_ARM_THM_MOVT_ABS:
     relocR_ARM_THM_MOVT_ABS(location, relocVAddress, targetVAddress, addend);
     break;
+  case R_ARM_PREL31:
+    relocR_ARM_PREL31(location, relocVAddress, targetVAddress, addend,
+                     addressesThumb);
+    break;
   default:
     return make_unhandled_reloc_error();
   }

diff --git a/lld/test/elf/ARM/rel-arm-prel31.test b/lld/test/elf/ARM/rel-arm-prel31.test
@@ -0,0 +1,48 @@
+# Check handling of R_ARM_PREL31 relocation.
+# RUN: yaml2obj -format=elf %s > %t-o.o
+# RUN: lld -flavor gnu -target arm -m armelf_linux_eabi -Bstatic \
+# RUN: --noinhibit-exec %t-o.o -o %t
+# RUN: llvm-objdump -s -t %t | FileCheck %s
+
+# CHECK: Contents of section .ARM.extab:
+# CHECK:  4000a4 b1ffff7f
+# CHECK: SYMBOL TABLE:
+# CHECK: 00000000         *UND*	00000000
+# CHECK: 00400054 g     F .text	00000050 __gxx_personality_v0
+
+---
+FileHeader:
+  Class:           ELFCLASS32
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_ARM
+  Flags:           [ EF_ARM_EABI_VER5 ]
+Sections:
+  - Name:            .ARM.extab
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC ]
+    AddressAlign:    0x4
+    Content:         0000000084019701B0B0B008FFFF01080E2432003A040000
+  - Name:            .rel.ARM.extab
+    Type:            SHT_REL
+    Link:            .symtab
+    AddressAlign:    0x4
+    Info:            .ARM.extab
+    Relocations:
+      - Offset:          0
+        Symbol:          __gxx_personality_v0
+        Type:            R_ARM_PREL31
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x4
+    Content:         80B400AF00231846BD465DF8047B704780B582B000AF3B1D1846FFF7FEFFFFF7FEFFFFF7FEFF0420FFF7FEFF0346184601230360002240F20001C0F20001FFF7FEFF3B1D1846FFF7FEFFFFF7FEFF00BF
+Symbols:
+  Local:
+  Global:
+    - Name:            __gxx_personality_v0
+      Type:            STT_FUNC
+      Section:         .text
+      Value:           0x1
+...
+
diff --git a/lld/test/elf/ARM/rel-rel32.test b/lld/test/elf/ARM/rel-rel32.test
@@ -0,0 +1,97 @@
+# Check handling of R_ARM_REL32 relocation.
+# RUN: yaml2obj -format=elf %s > %t-o.o
+# RUN: lld -flavor gnu -target arm -m armelf_linux_eabi -Bstatic \
+# RUN: --noinhibit-exec %t-o.o -o %t
+# RUN: llvm-objdump -s -t %t | FileCheck %s
+
+# CHECK: Contents of section .text:
+# CHECK-NEXT: 400074 80b400af 880f0000
+# CHECK: SYMBOL TABLE:
+# CHECK: 00400074 g     F .text	00000004 main
+# CHECK: 00401000 g       .bss	00000004 _myref
+
+---
+---
+FileHeader:
+  Class:           ELFCLASS32
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_ARM
+  Flags:           [ EF_ARM_EABI_VER5 ]
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x0000000000000004
+    Content:         80B400AF0000000000231846BD465DF8047B7047
+  - Name:            .rel.text
+    Type:            SHT_REL
+    Link:            .symtab
+    AddressAlign:    0x0000000000000004
+    Info:            .text
+    Relocations:
+      - Offset:          0x0000000000000004
+        Symbol:          _myref
+        Type:            R_ARM_REL32
+  - Name:            .data
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC ]
+    AddressAlign:    0x0000000000000001
+    Content:         ''
+  - Name:            .bss
+    Type:            SHT_NOBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC ]
+    AddressAlign:    0x0000000000000004
+    Content:         '00474343'
+  - Name:            .comment
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_MERGE, SHF_STRINGS ]
+    AddressAlign:    0x0000000000000001
+    Content:         004743433A202863726F7373746F6F6C2D4E47206C696E61726F2D312E31332E312D342E392D323031342E3039202D204C696E61726F2047434320342E392D323031342E30392920342E392E32203230313430393034202870726572656C656173652900
+  - Name:            .note.GNU-stack
+    Type:            SHT_PROGBITS
+    AddressAlign:    0x0000000000000001
+    Content:         ''
+  - Name:            .ARM.attributes
+    Type:            SHT_ARM_ATTRIBUTES
+    AddressAlign:    0x0000000000000001
+    Content:         4134000000616561626900012A00000005372D4100060A0741080109020A041204140115011703180119011A021B031C011E062201
+Symbols:
+  Local:
+    - Name:            test.c
+      Type:            STT_FILE
+    - Name:            .text
+      Type:            STT_SECTION
+      Section:         .text
+    - Name:            .data
+      Type:            STT_SECTION
+      Section:         .data
+    - Name:            .bss
+      Type:            STT_SECTION
+      Section:         .bss
+    - Name:            '$d'
+      Section:         .text
+      Value:           0x0000000000000004
+    - Name:            '$t'
+      Section:         .text
+      Value:           0x0000000000000008
+    - Name:            .note.GNU-stack
+      Type:            STT_SECTION
+      Section:         .note.GNU-stack
+    - Name:            .comment
+      Type:            STT_SECTION
+      Section:         .comment
+    - Name:            .ARM.attributes
+      Type:            STT_SECTION
+      Section:         .ARM.attributes
+  Global:
+    - Name:            _myref
+      Type:            STT_OBJECT
+      Section:         .bss
+      Size:            0x0000000000000004
+    - Name:            main
+      Type:            STT_FUNC
+      Section:         .text
+      Value:           0x0000000000000001
+      Size:            0x0000000000000014
+...