[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

1 files changed, 81 insertions, 1 deletions

diff --git a/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationHandler.cpp b/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationHandler.cpp
index 938210f8f49..c99015275b6 100644
--- 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();
   }