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dave-bartolomeodave-bartolomeo
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C++: Simple constant analysis
This change moves the simple constant analysis that was used by the const_func test into a pyrameterized module for use on any stage of the IR. This will be used to detect unreachable code.
1 parent 6a11ef5 commit 59fc77f

11 files changed

Lines changed: 143 additions & 22 deletions

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‎config/identical-files.json‎

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"cpp/ql/src/semmle/code/cpp/ir/implementation/raw/gvn/ValueNumbering.qll",
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"cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/gvn/ValueNumbering.qll",
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"cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/gvn/ValueNumbering.qll"
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],
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"C++ IR ConstantAnalysis": [
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"cpp/ql/src/semmle/code/cpp/ir/implementation/raw/constant/ConstantAnalysis.qll",
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"cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/constant/ConstantAnalysis.qll",
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"cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/constant/ConstantAnalysis.qll"
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],
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"C++ IR PrintConstantAnalysis": [
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"cpp/ql/src/semmle/code/cpp/ir/implementation/raw/constant/PrintConstantAnalysis.qll",
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"cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/constant/PrintConstantAnalysis.qll",
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"cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/constant/PrintConstantAnalysis.qll"
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]
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}

‎cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/constant/ConstantAnalysis.qll‎

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private import internal.ConstantAnalysisInternal
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import semmle.code.cpp.ir.internal.IntegerConstant
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private import IR
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language[monotonicAggregates]
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IntValue getConstantValue(Instruction instr) {
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result = instr.(IntegerConstantInstruction).getValue().toInt() or
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exists(BinaryInstruction binInstr, IntValue left, IntValue right |
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binInstr = instr and
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left = getConstantValue(binInstr.getLeftOperand()) and
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right = getConstantValue(binInstr.getRightOperand()) and
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(
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binInstr instanceof AddInstruction and result = add(left, right) or
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binInstr instanceof SubInstruction and result = sub(left, right) or
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binInstr instanceof MulInstruction and result = mul(left, right) or
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binInstr instanceof DivInstruction and result = div(left, right)
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)
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) or
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exists(UnaryInstruction unaryInstr, IntValue src |
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unaryInstr = instr and
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src = getConstantValue(unaryInstr.getOperand()) and
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(
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unaryInstr instanceof NegateInstruction and result = neg(src)
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)
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) or
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result = getConstantValue(instr.(CopyInstruction).getSourceValue()) or
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exists(PhiInstruction phi |
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phi = instr and
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result = max(PhiOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction())) and
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result = min(PhiOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction()))
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)
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}

‎cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/constant/PrintConstantAnalysis.qll‎

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private import internal.ConstantAnalysisInternal
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private import semmle.code.cpp.ir.internal.IntegerConstant
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private import ConstantAnalysis
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import IR
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private class ConstantAnalysisPropertyProvider extends IRPropertyProvider {
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override string getInstructionProperty(Instruction instr, string key) {
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key = "ConstantValue" and
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result = getValue(getConstantValue(instr)).toString()
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}
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}

‎cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/constant/internal/ConstantAnalysisInternal.qll‎

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import semmle.code.cpp.ir.implementation.aliased_ssa.IR as IR

‎cpp/ql/src/semmle/code/cpp/ir/implementation/raw/constant/ConstantAnalysis.qll‎

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private import internal.ConstantAnalysisInternal
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import semmle.code.cpp.ir.internal.IntegerConstant
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private import IR
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language[monotonicAggregates]
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IntValue getConstantValue(Instruction instr) {
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result = instr.(IntegerConstantInstruction).getValue().toInt() or
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exists(BinaryInstruction binInstr, IntValue left, IntValue right |
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binInstr = instr and
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left = getConstantValue(binInstr.getLeftOperand()) and
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right = getConstantValue(binInstr.getRightOperand()) and
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(
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binInstr instanceof AddInstruction and result = add(left, right) or
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binInstr instanceof SubInstruction and result = sub(left, right) or
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binInstr instanceof MulInstruction and result = mul(left, right) or
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binInstr instanceof DivInstruction and result = div(left, right)
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)
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) or
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exists(UnaryInstruction unaryInstr, IntValue src |
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unaryInstr = instr and
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src = getConstantValue(unaryInstr.getOperand()) and
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(
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unaryInstr instanceof NegateInstruction and result = neg(src)
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)
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) or
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result = getConstantValue(instr.(CopyInstruction).getSourceValue()) or
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exists(PhiInstruction phi |
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phi = instr and
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result = max(PhiOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction())) and
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result = min(PhiOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction()))
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)
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}

‎cpp/ql/src/semmle/code/cpp/ir/implementation/raw/constant/PrintConstantAnalysis.qll‎

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private import internal.ConstantAnalysisInternal
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private import semmle.code.cpp.ir.internal.IntegerConstant
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private import ConstantAnalysis
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import IR
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private class ConstantAnalysisPropertyProvider extends IRPropertyProvider {
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override string getInstructionProperty(Instruction instr, string key) {
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key = "ConstantValue" and
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result = getValue(getConstantValue(instr)).toString()
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}
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}

‎cpp/ql/src/semmle/code/cpp/ir/implementation/raw/constant/internal/ConstantAnalysisInternal.qll‎

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import semmle.code.cpp.ir.implementation.raw.IR as IR

‎cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/constant/ConstantAnalysis.qll‎

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private import internal.ConstantAnalysisInternal
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import semmle.code.cpp.ir.internal.IntegerConstant
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private import IR
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language[monotonicAggregates]
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IntValue getConstantValue(Instruction instr) {
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result = instr.(IntegerConstantInstruction).getValue().toInt() or
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exists(BinaryInstruction binInstr, IntValue left, IntValue right |
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binInstr = instr and
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left = getConstantValue(binInstr.getLeftOperand()) and
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right = getConstantValue(binInstr.getRightOperand()) and
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(
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binInstr instanceof AddInstruction and result = add(left, right) or
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binInstr instanceof SubInstruction and result = sub(left, right) or
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binInstr instanceof MulInstruction and result = mul(left, right) or
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binInstr instanceof DivInstruction and result = div(left, right)
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)
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) or
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exists(UnaryInstruction unaryInstr, IntValue src |
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unaryInstr = instr and
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src = getConstantValue(unaryInstr.getOperand()) and
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(
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unaryInstr instanceof NegateInstruction and result = neg(src)
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)
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) or
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result = getConstantValue(instr.(CopyInstruction).getSourceValue()) or
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exists(PhiInstruction phi |
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phi = instr and
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result = max(PhiOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction())) and
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result = min(PhiOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction()))
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)
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}

‎cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/constant/PrintConstantAnalysis.qll‎

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private import internal.ConstantAnalysisInternal
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private import semmle.code.cpp.ir.internal.IntegerConstant
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private import ConstantAnalysis
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import IR
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private class ConstantAnalysisPropertyProvider extends IRPropertyProvider {
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override string getInstructionProperty(Instruction instr, string key) {
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key = "ConstantValue" and
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result = getValue(getConstantValue(instr)).toString()
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}
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}

‎cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/constant/internal/ConstantAnalysisInternal.qll‎

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import semmle.code.cpp.ir.implementation.unaliased_ssa.IR as IR

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