yetangitu/ghidra
1
0
Fork 0
mirror of https://github.com/NationalSecurityAgency/ghidra.git synced 2025-10-05 02:39:44 +02:00
Code Issues Releases Wiki Activity

GP-3962 fix to correct function bodies with instructions that branch

Browse source 
into the delay slot
This commit is contained in:
emteere 2023-10-25 21:19:20 +00:00
parent 10cc91bd8e
commit 6f9d2c3b78
2 changed files with 19 additions and 17 deletions
Download patch file Download diff file Expand all files Collapse all files

9
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/code/InstructionDB.java
View file

@ -218,6 +218,7 @@ public class InstructionDB extends CodeUnitDB implements Instruction, Instructio
if (alignment < 1) { if (alignment < 1) {
alignment = 1; alignment = 1;
} }
do { do {
// skip past delay slot instructions // skip past delay slot instructions
try { try {
@ -228,8 +229,16 @@ public class InstructionDB extends CodeUnitDB implements Instruction, Instructio
catch (AddressOverflowException e) { catch (AddressOverflowException e) {
return null; return null;
} }
// if an instruction is in a delay slot and has references to it,
// consider this the fallfrom instruction
if (instr != null && instr.isInDelaySlot() && instr.hasFallthrough()) {
if (program.getSymbolTable().hasSymbol(instr.getMinAddress())) {
break;
}
}
} }
while (instr != null && instr.isInDelaySlot()); while (instr != null && instr.isInDelaySlot());
if (instr == null) { if (instr == null) {
return null; return null;
} }

25
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/block/FollowFlow.java
View file

@ -349,6 +349,10 @@ public class FollowFlow {
} }
} }
// Delay adding instructions in delay slots to the functions body
// until the end. This allows for branches into the delay slot to be handled correctly.
AddressSet delaySlotSet = new AddressSet();
while (!monitor.isCancelled() && !instructionStack.isEmpty()) { while (!monitor.isCancelled() && !instructionStack.isEmpty()) {
codeUnit = instructionStack.pop(); codeUnit = instructionStack.pop();
@ -368,35 +372,24 @@ public class FollowFlow {
continue; continue;
} }
// If code unit is a delay-slot instruction, backup to delayed instruction
Instruction instr = currentInstr; Instruction instr = currentInstr;
// while (instr.isInDelaySlot()) {
// Address fallFrom = instr.getFallFrom();
// if (fallFrom == null) {
// // assumes delay slot instructions have no flow
// flowAddressSet.addRange(instr.getMinAddress(),
// currentInstr.getMaxAddress());
// break;
// }
// instr = program.getListing().getInstructionContaining(fallFrom);
// }
// if (instr.isInDelaySlot())
// continue; // unable to find non-delay-slot instruction
// currentInstr = instr;
// handle instruction - include associated delay slot instructions // handle instruction with delay slot instructions
Address end = instr.getMaxAddress(); Address end = instr.getMaxAddress();
int delaySlotDepth = instr.getDelaySlotDepth(); int delaySlotDepth = instr.getDelaySlotDepth();
for (int i = 0; i < delaySlotDepth; i++) { for (int i = 0; i < delaySlotDepth; i++) {
instr = instr.getNext(); instr = instr.getNext();
if (instr == null) if (instr == null)
break; break;
end = instr.getMaxAddress(); delaySlotSet.add(instr.getMinAddress(),instr.getMaxAddress());
} }
flowAddressSet.addRange(currentInstr.getMinAddress(), end); flowAddressSet.addRange(currentInstr.getMinAddress(), end);
followInstruction(instructionStack, flowAddressSet, currentInstr); followInstruction(instructionStack, flowAddressSet, currentInstr);
} }
// add in any instructions that were in a delayslot
flowAddressSet.add(delaySlotSet);
} // followCode } // followCode
/** /**