From f2f2438290d9730a5565e607599a24b23ae4a586 Mon Sep 17 00:00:00 2001
From: an7s <an7s@git.zephyr-software.com>
Date: Thu, 1 Dec 2011 18:49:57 +0000
Subject: [PATCH] Handling reg*constant now
Former-commit-id: ef72706f82996297dc76dfbd32d5e6821b30d7d4
---
libtransform/src/integertransform.cpp | 55 +++++++++++++--------------
1 file changed, 26 insertions(+), 29 deletions(-)
diff --git a/libtransform/src/integertransform.cpp b/libtransform/src/integertransform.cpp
index ee36b42ae..b493eb224 100644
--- a/libtransform/src/integertransform.cpp
+++ b/libtransform/src/integertransform.cpp
@@ -223,7 +223,7 @@ void IntegerTransform::addOverflowCheckNoFlag(Instruction_t *p_instruction, cons
}
else if (leaPattern.isRegisterTimesConstant())
{
-cerr << "IntegerTransform::addOverflowCheckNoFlag(): lea reg*constant pattern: not yet handled" << endl; return;
+//cerr << "IntegerTransform::addOverflowCheckNoFlag(): lea reg*constant pattern: not yet handled" << endl; return;
Register::RegisterName reg1 = leaPattern.getRegister1();
int value = leaPattern.getConstant();
Register::RegisterName target = getTargetRegister(p_instruction);
@@ -330,9 +330,6 @@ void IntegerTransform::addOverflowCheckNoFlag_RegPlusConstant(Instruction_t *p_i
{
cerr << "integertransform: reg+constant: register: " << Register::toString(p_reg1) << " constant: " << p_constantValue << " target register: " << Register::toString(p_reg3) << " annotation: " << p_annotation.toString() << endl;
- cerr << "integertransform: reg+constant: register: skipping " << endl;
- return;
-
//
// Original instruction is of the form:
// lea r3, [r1+constant]
@@ -393,54 +390,54 @@ void IntegerTransform::addOverflowCheckNoFlag_RegPlusConstant(Instruction_t *p_i
void IntegerTransform::addOverflowCheckNoFlag_RegTimesConstant(Instruction_t *p_instruction, const MEDS_InstructionCheckAnnotation& p_annotation, const Register::RegisterName& p_reg1, const int p_constantValue, const Register::RegisterName& p_reg3)
{
- cerr << "integertransform: reg+constant: register: " << Register::toString(p_reg1) << " constant: " << p_constantValue << " target register: " << Register::toString(p_reg3) << " annotation: " << p_annotation.toString() << endl;
-// should we even attempt to instrument if we're not sure about the signedness for this pattern?
-
-// need to use the correct PC (the one for the original lea instruction) when printing detector message
-
- // Original instruction is of the form: lea r3, [r1+constant]
+ cerr << "integertransform: reg*constant: register: " << Register::toString(p_reg1) << " constant: " << p_constantValue << " target register: " << Register::toString(p_reg3) << " annotation: " << p_annotation.toString() << endl;
+ //
+ // Original instruction is of the form:
+ // lea r3, [r1*constant]
+ //
// Instrumentation:
// pushf ; save flags
- // add r1, constant ; r1 = r1 + constant;
+ // mov r3, r1 ; r3 = r1
+ // imul r3, constant ; r3 = r1 * constant;
// <check for overflow> ; reuse overflow code
- // mov r3, r1 ; r3 = r1 (replaces lea r3, [r1+constant])
- // ; possible optimization: do nothing if r3 == r1
// popf ; restore flags
//
-
+ // Note: if r3 == r1, code still works (though inefficiently)
+ //
db_id_t fileID = p_instruction->GetAddress()->GetFileID();
Function_t* func = p_instruction->GetFunction();
Instruction_t* fallthrough = p_instruction->GetFallthrough();
Instruction_t* pushf_i = allocateNewInstruction(fileID, func);
- Instruction_t* mulR1Constant_i = allocateNewInstruction(fileID, func);
Instruction_t* movR3R1_i = allocateNewInstruction(fileID, func);
+ Instruction_t* mulR3Constant_i = allocateNewInstruction(fileID, func);
Instruction_t* popf_i = allocateNewInstruction(fileID, func);
- MEDS_InstructionCheckAnnotation mulR1Constant_annot;
- mulR1Constant_annot.setValid();
- mulR1Constant_annot.setBitWidth(32);
- mulR1Constant_annot.setOverflow();
+ MEDS_InstructionCheckAnnotation mulR3Constant_annot;
+ mulR3Constant_annot.setValid();
+ mulR3Constant_annot.setBitWidth(32);
+ mulR3Constant_annot.setOverflow();
if (p_annotation.isSigned())
- mulR1Constant_annot.setSigned();
+ mulR3Constant_annot.setSigned();
else if (p_annotation.isUnsigned())
- mulR1Constant_annot.setUnsigned();
+ mulR3Constant_annot.setUnsigned();
else
- mulR1Constant_annot.setUnknownSign();
+ mulR3Constant_annot.setUnknownSign();
string msg = "Originally: " + p_instruction->getDisassembly();
- addPushf(pushf_i, mulR1Constant_i);
+ AddressID_t *originalAddress = p_instruction->GetAddress();
+
+ addPushf(pushf_i, movR3R1_i);
Instruction_t* originalInstrumentInstr = carefullyInsertBefore(p_instruction, pushf_i);
- pushf_i->SetFallthrough(mulR1Constant_i); // do I need this?
+ pushf_i->SetFallthrough(movR3R1_i); // do I need this?
- addMulRegisterConstant(mulR1Constant_i, p_reg1, p_constantValue, movR3R1_i);
- addMovRegisters(movR3R1_i, p_reg3, p_reg1, popf_i);
+ addMovRegisters(movR3R1_i, p_reg3, p_reg1, mulR3Constant_i);
+ addMulRegisterConstant(mulR3Constant_i, p_reg3, p_constantValue, popf_i);
addPopf(popf_i, fallthrough);
- movR3R1_i->SetComment(msg);
- addOverflowCheck(mulR1Constant_i, mulR1Constant_annot);
- return;
+ mulR3Constant_i->SetComment(msg);
+ addOverflowCheck(mulR3Constant_i, mulR3Constant_annot, originalAddress);
}
void IntegerTransform::handleTruncation(Instruction_t *p_instruction, const MEDS_InstructionCheckAnnotation& p_annotation)
--
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