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Fixing statetrace to work with 32 bit SPARC processes, as well as rewritting it's single stepping code.

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--HG--
extra : convert_revision : 69b1668a850519ab98b02c525ec41ff727eb6036
This commit is contained in:
Gabe Black 2007-03-05 20:54:20 -05:00
parent 68ad153309
commit 9b72ff8290
5 changed files with 169 additions and 81 deletions
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209
util/statetrace/arch/tracechild_sparc.cc
View file

@ -1,5 +1,5 @@
/*
* Copyright (c) 2006 The Regents of The University of Michigan
* Copyright (c) 2006-2007 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@ -151,7 +151,6 @@ int64_t getRegs(regs & myregs, fpu & myfpu,
bool SparcTraceChild::update(int pid)
{
static const int stackBias = 2047;
memcpy(&oldregs, &theregs, sizeof(regs));
memcpy(&oldfpregs, &thefpregs, sizeof(fpu));
memcpy(oldLocals, locals, 8 * sizeof(uint64_t));
@ -161,7 +160,8 @@ bool SparcTraceChild::update(int pid)
cerr << "Update failed" << endl;
return false;
}
uint64_t StackPointer = getRegVal(O6);
uint64_t StackPointer = getSP();
const int stackBias = (StackPointer % 1) ? 2047 : 0;
for(unsigned int x = 0; x < 8; x++)
{
locals[x] = ptrace(PTRACE_PEEKTEXT, pid,
@ -182,8 +182,76 @@ SparcTraceChild::SparcTraceChild()
regDiffSinceUpdate[x] = false;
}
int SparcTraceChild::getTargets(uint32_t inst, uint64_t pc, uint64_t npc,
uint64_t &target1, uint64_t &target2)
{
//We can identify the instruction categories we care about using the top
//10 bits of the instruction, excluding the annul bit in the 3rd most
//significant bit position and the condition field. We'll call these
//bits the "sig" for signature.
uint32_t sig = (inst >> 22) & 0x307;
uint32_t cond = (inst >> 25) & 0xf;
bool annul = (inst & (1 << 29));
//Check if it's a ba...
bool ba = (cond == 0x8) &&
(sig == 0x1 || sig == 0x2 || sig == 0x5 || sig == 0x6);
//or a bn...
bool bn = (cond == 0x0) &&
(sig == 0x1 || sig == 0x2 || sig == 0x5 || sig == 0x6);
//or a bcc
bool bcc = (cond & 0x7) &&
(sig == 0x1 || sig == 0x2 || sig == 0x3 || sig == 0x5 || sig == 0x6);
if(annul)
{
if(bcc)
{
target1 = npc;
target2 = npc + 4;
return 2;
}
else if(ba)
{
//This branches immediately to the effective address of the branch
//which we'll have to calculate.
uint64_t disp = 0;
int64_t extender = 0;
//Figure out how big the displacement field is, and grab the bits
if(sig == 0x1 || sig == 0x5)
{
disp = inst & ((1 << 19) - 1);
extender = 1 << 18;
}
else
{
disp = inst & ((1 << 22) - 1);
extender = 1 << 21;
}
//This does sign extension, believe it or not.
disp = (disp ^ extender) - extender;
//Multiply the displacement by 4. I'm assuming the compiler is
//smart enough to turn this into a shift.
disp *= 4;
target1 = pc + disp;
}
else if(bn)
target1 = npc + 4;
else
target1 = npc;
return 1;
}
else
{
target1 = npc;
return 1;
}
}
bool SparcTraceChild::step()
{
//Increment the count of the number of instructions executed
instructions++;
//Two important considerations are that the address of the instruction
//being breakpointed should be word (64bit) aligned, and that both the
//next instruction and the instruction after that need to be breakpointed
@ -193,6 +261,8 @@ bool SparcTraceChild::step()
* Useful constants
*/
const static uint64_t breakInst = 0x91d02001;
const static uint64_t lowBreakInst = breakInst;
const static uint64_t highBreakInst = breakInst << 32;
const static uint64_t breakWord = breakInst | (breakInst << 32);
const static uint64_t lowMask = 0xFFFFFFFFULL;
const static uint64_t highMask = lowMask << 32;
@ -212,60 +282,39 @@ bool SparcTraceChild::step()
bool unalignedNPC = nextPC & 7;
uint64_t alignedNPC = nextPC & (~7);
/*
* Store the original contents of the child process's memory
*/
originalInst = ptrace(PTRACE_PEEKTEXT, pid, alignedNPC, 0);
//Save a ptrace call if we can
if(unalignedNPC)
{
originalAnnulInst = ptrace(PTRACE_PEEKTEXT, pid, alignedNPC+8, 0);
}
//Get the current instruction
uint64_t curInst = ptrace(PTRACE_PEEKTEXT, pid, alignedPC);
curInst = unalignedPC ? (curInst & 0xffffffffULL) : (curInst >> 32);
uint64_t bp1, bp2;
int numTargets = getTargets(curInst, currentPC, nextPC, bp1, bp2);
assert(numTargets == 1 || numTargets == 2);
bool unalignedBp1 = bp1 & 7;
uint64_t alignedBp1 = bp1 & (~7);
bool unalignedBp2 = bp2 & 7;
uint64_t alignedBp2 = bp2 & (~7);
uint64_t origBp1, origBp2;
/*
* Prepare breakpointed copies of child processes memory
* Set the first breakpoint
*/
uint64_t newInst, newAnnulInst;
//If the current instruction is in the same word as the npc
if(alignedPC == alignedNPC)
{
//Make sure we only replace the other part
if(unalignedPC)
newInst = (originalInst & lowMask) | (breakWord & highMask);
else
newInst = (originalInst & highMask) | (breakWord & lowMask);
}
else
{
//otherwise replace the whole thing
newInst = breakWord;
}
//If the current instruction is in the same word as the word after
//the npc
if(alignedPC == alignedNPC+8)
{
//Make sure we only replace the other part
if(unalignedPC)
newAnnulInst = (originalAnnulInst & lowMask) | (breakWord & highMask);
else
newAnnulInst = (originalAnnulInst & highMask) | (breakWord & lowMask);
}
else
{
//otherwise replace the whole thing
newAnnulInst = breakWord;
}
/*
* Stuff the breakpoint instructions into the child's address space.
*/
//Replace the word at npc
if(ptrace(PTRACE_POKETEXT, pid, alignedNPC, newInst) != 0)
origBp1 = ptrace(PTRACE_PEEKTEXT, pid, alignedBp1, 0);
uint64_t newBp1 = origBp1;
newBp1 &= unalignedBp1 ? highMask : lowMask;
newBp1 |= unalignedBp1 ? lowBreakInst : highBreakInst;
if(ptrace(PTRACE_POKETEXT, pid, alignedBp1, newBp1) != 0)
cerr << "Poke failed" << endl;
//Replace the next word, if necessary
if(unalignedNPC)
/*
* Set the second breakpoint if necessary
*/
if(numTargets == 2)
{
if(ptrace(PTRACE_POKETEXT, pid, alignedNPC+8, newAnnulInst) != 0)
origBp2 = ptrace(PTRACE_PEEKTEXT, pid, alignedBp2, 0);
uint64_t newBp2 = origBp2;
newBp2 &= unalignedBp2 ? highMask : lowMask;
newBp2 |= unalignedBp2 ? lowBreakInst : highBreakInst;
if(ptrace(PTRACE_POKETEXT, pid, alignedBp2, newBp2) != 0)
cerr << "Poke failed" << endl;
}
@ -285,16 +334,16 @@ bool SparcTraceChild::step()
update(pid);
/*
* Put back the original contents of the childs address space
* Put back the original contents of the childs address space in the
* reverse order.
*/
if(ptrace(PTRACE_POKETEXT, pid, alignedNPC, originalInst) != 0)
cerr << "Repoke failed" << endl;
if(unalignedNPC)
if(numTargets == 2)
{
if(ptrace(PTRACE_POKETEXT, pid, alignedNPC+8, originalAnnulInst) != 0)
cerr << "Repoke failed" << endl;
if(ptrace(PTRACE_POKETEXT, pid, alignedBp2, origBp2) != 0)
cerr << "Poke failed" << endl;
}
return true;
if(ptrace(PTRACE_POKETEXT, pid, alignedBp1, origBp1) != 0)
cerr << "Poke failed" << endl;
}
int64_t SparcTraceChild::getRegVal(int num)
@ -315,39 +364,56 @@ char * SparcTraceChild::printReg(int num)
ostream & SparcTraceChild::outputStartState(ostream & os)
{
bool v8 = false;
uint64_t sp = getSP();
if(sp % 1)
{
os << "Detected a 64 bit executable.\n";
v8 = false;
}
else
{
os << "Detected a 32 bit executable.\n";
v8 = true;
}
uint64_t pc = getPC();
char obuf[1024];
sprintf(obuf, "Initial stack pointer = 0x%016llx\n", sp);
os << obuf;
sprintf(obuf, "Initial program counter = 0x%016llx\n", pc);
os << obuf;
//Take out the stack bias
sp += 2047;
if(!v8)
{
//Take out the stack bias
sp += 2047;
}
//Output the window save area
for(unsigned int x = 0; x < 16; x++)
{
uint64_t regspot = ptrace(PTRACE_PEEKDATA, pid, sp, 0);
if(v8) regspot = regspot >> 32;
sprintf(obuf, "0x%016llx: Window save %d = 0x%016llx\n",
sp, x+1, regspot);
os << obuf;
sp += 8;
sp += v8 ? 4 : 8;
}
//Output the argument count
uint64_t cargc = ptrace(PTRACE_PEEKDATA, pid, sp, 0);
if(v8) cargc = cargc >> 32;
sprintf(obuf, "0x%016llx: Argc = 0x%016llx\n", sp, cargc);
os << obuf;
sp += 8;
sp += v8 ? 4 : 8;
//Output argv pointers
int argCount = 0;
uint64_t cargv;
do
{
cargv = ptrace(PTRACE_PEEKDATA, pid, sp, 0);
if(v8) cargv = cargv >> 32;
sprintf(obuf, "0x%016llx: argv[%d] = 0x%016llx\n",
sp, argCount++, cargv);
os << obuf;
sp += 8;
sp += v8 ? 4 : 8;
} while(cargv);
//Output the envp pointers
int envCount = 0;
@ -355,20 +421,23 @@ ostream & SparcTraceChild::outputStartState(ostream & os)
do
{
cenvp = ptrace(PTRACE_PEEKDATA, pid, sp, 0);
if(v8) cenvp = cenvp >> 32;
sprintf(obuf, "0x%016llx: envp[%d] = 0x%016llx\n",
sp, envCount++, cenvp);
os << obuf;
sp += 8;
sp += v8 ? 4 : 8;
} while(cenvp);
uint64_t auxType, auxVal;
do
{
auxType = ptrace(PTRACE_PEEKDATA, pid, sp, 0);
sp += 8;
if(v8) auxType = auxType >> 32;
sp += (v8 ? 4 : 8);
auxVal = ptrace(PTRACE_PEEKDATA, pid, sp, 0);
sp += 8;
if(v8) auxVal = auxVal >> 32;
sp += (v8 ? 4 : 8);
sprintf(obuf, "0x%016llx: Auxiliary vector = {0x%016llx, 0x%016llx}\n",
sp - 16, auxType, auxVal);
sp - 8, auxType, auxVal);
os << obuf;
} while(auxType != 0 || auxVal != 0);
//Print out the argument strings, environment strings, and file name.
@ -380,7 +449,7 @@ ostream & SparcTraceChild::outputStartState(ostream & os)
{
buf = ptrace(PTRACE_PEEKDATA, pid, sp, 0);
char * cbuf = (char *)&buf;
for(int x = 0; x < sizeof(uint64_t); x++)
for(int x = 0; x < sizeof(uint32_t); x++)
{
if(cbuf[x])
current += cbuf[x];
@ -393,7 +462,7 @@ ostream & SparcTraceChild::outputStartState(ostream & os)
currentStart = sp + x + 1;
}
}
sp += 8;
sp += (v8 ? 4 : 8);
clearedInitialPadding = clearedInitialPadding || buf != 0;
} while(!clearedInitialPadding || buf != 0);
return os;

8
util/statetrace/arch/tracechild_sparc.hh
View file

@ -1,5 +1,5 @@
/*
* Copyright (c) 2006 The Regents of The University of Michigan
* Copyright (c) 2006-2007 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@ -78,6 +78,12 @@ private:
int64_t oldInputs[8];
bool regDiffSinceUpdate[numregs];
//This calculates where the pc might go after the current instruction.
//while this equals npc for most instructions, it doesn't for all of
//them. The return value is the number of actual potential targets.
int getTargets(uint32_t inst, uint64_t pc, uint64_t npc,
uint64_t &target1, uint64_t &target2);
protected:
bool update(int pid);

12
util/statetrace/statetrace.cc
View file

@ -1,5 +1,5 @@
/*
* Copyright (c) 2006 The Regents of The University of Michigan
* Copyright (c) 2006-2007 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@ -145,9 +145,13 @@ int main(int argc, char * argv[], char * envp[])
return 1;
}
}
for(unsigned int x = startProgramArgs; x < argc; x++)
args += argv[x];
if(!child->startTracing(argv[startProgramArgs], args.c_str()))
/*for(unsigned int x = startProgramArgs; x < argc; x++)
{
cout << "Adding argument " << argv[x];
args += string(" ") + argv[x];
}*/
if(!child->startTracing(argv[startProgramArgs],
argv + startProgramArgs))
{
cerr << "Couldn't start target program" << endl;
return 1;

13
util/statetrace/tracechild.cc
View file

@ -1,5 +1,5 @@
/*
* Copyright (c) 2006 The Regents of The University of Michigan
* Copyright (c) 2006-2007 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@ -36,8 +36,9 @@
using namespace std;
bool TraceChild::startTracing(const char * pathToFile, const char * arg)
bool TraceChild::startTracing(const char * pathToFile, char * const argv[])
{
instructions = 0;
pid = fork();
if(pid == -1)
{
@ -53,7 +54,7 @@ bool TraceChild::startTracing(const char * pathToFile, const char * arg)
ptrace(PTRACE_TRACEME, 0, 0, 0);
//Start the program to trace
execl(pathToFile, arg);
execv(pathToFile, argv);
//We should never get here, so this is an error!
return false;
@ -121,6 +122,8 @@ bool TraceChild::doWait()
{
cerr << "Program exited! Exit status is "
<< WEXITSTATUS(wait_val) << endl;
cerr << "Executed " << instructions
<< " instructions." << endl;
tracing = false;
return false;
}
@ -132,6 +135,8 @@ bool TraceChild::doWait()
if(WCOREDUMP(wait_val))
cerr << "Program core dumped!" << endl;
tracing = false;
cerr << "Executed " << instructions
<< " instructions." << endl;
return false;
}
if(WIFSTOPPED(wait_val) && WSTOPSIG(wait_val) != SIGTRAP)
@ -139,6 +144,8 @@ bool TraceChild::doWait()
cerr << "Program stopped by signal "
<< WSTOPSIG(wait_val) << endl;
tracing = false;
cerr << "Executed " << instructions
<< " instructions." << endl;
return false;
}
return true;

8
util/statetrace/tracechild.hh
View file

@ -1,5 +1,5 @@
/*
* Copyright (c) 2006 The Regents of The University of Michigan
* Copyright (c) 2006-2007 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@ -37,11 +37,13 @@ class TraceChild : public RegState
{
protected:
int pid;
uint64_t instructions;
bool tracing;
public:
TraceChild() : tracing(false)
TraceChild() : tracing(false), instructions(0)
{;}
virtual bool startTracing(const char * pathToFile, const char * arg);
virtual bool startTracing(const char * pathToFile,
char * const argv[]);
virtual bool stopTracing();
virtual bool step();
virtual uint64_t getPC() = 0;