Ignore R_ARM_V4BX relocation for ARM

Kingcom · Jan 7, 2018 · c082e18 · c082e18
1 parent a1b9d43
commit c082e18
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Showing 4 changed files with 13 additions and 0 deletions.
diff --git a/Archs/ARM/ArmRelocator.cpp b/Archs/ARM/ArmRelocator.cpp
@@ -10,6 +10,13 @@ inline int signExtend(int value, int bitsLength)
 	return (value << (32-bitsLength)) >> (32-bitsLength);
 }
 
+bool ArmElfRelocator::isDummyRelocationType(int type) const
+{
+	// R_ARM_V4BX marks the position of a bx opcode, and does not
+	// cause any actual relocations
+	return type == R_ARM_V4BX;
+}
+
 /*
 	S = symbol address
 	T = 1 if symbol is a thumb mode function, 0 otherwise

diff --git a/Archs/ARM/ArmRelocator.h b/Archs/ARM/ArmRelocator.h
@@ -8,13 +8,15 @@ enum {
 	R_ARM_CALL = 28,
 	R_ARM_JUMP24 = 29,
 	R_ARM_TARGET1 = 38,
+	R_ARM_V4BX = 40,
 };
 
 
 class ArmElfRelocator: public IElfRelocator
 {
 public:
 	ArmElfRelocator(bool arm9): arm9(arm9) { };
+	virtual bool isDummyRelocationType(int type) const;
 	virtual bool relocateOpcode(int type, RelocationData& data);
 	virtual void setSymbolAddress(RelocationData& data, int64_t symbolAddress, int symbolType);
 	virtual CAssemblerCommand* generateCtorStub(std::vector<ElfRelocatorCtor>& ctors);

diff --git a/Core/ELF/ElfRelocator.cpp b/Core/ELF/ElfRelocator.cpp
@@ -317,6 +317,9 @@ bool ElfRelocator::relocateFile(ElfRelocatorFile& file, int64_t& relocationAddre
 				loadRelocation(rel, relSection->getData(), relOffset, elf->isBigEndian());
 				int pos = rel.r_offset;
 
+				if (relocator->isDummyRelocationType(rel.getType()))
+					continue;
+
 				int symNum = rel.getSymbolNum();
 				if (symNum <= 0)
 				{

diff --git a/Core/ELF/ElfRelocator.h b/Core/ELF/ElfRelocator.h
@@ -15,6 +15,7 @@ class IElfRelocator
 {
 public:
 	virtual ~IElfRelocator() { };
+	virtual bool isDummyRelocationType(int type) const { return false; }
 	virtual bool relocateOpcode(int type, RelocationData& data) = 0;
 	virtual void setSymbolAddress(RelocationData& data, int64_t symbolAddress, int symbolType) = 0;
 	virtual CAssemblerCommand* generateCtorStub(std::vector<ElfRelocatorCtor>& ctors) { return nullptr; }