Java/C++: Move range util guard-controls predicates to shared pack.

This commit is contained in:
Anders Schack-Mulligen
2023-11-07 15:06:11 +01:00
parent f2ca52d951
commit 12cba7909b
8 changed files with 50 additions and 113 deletions

View File

@@ -35,32 +35,4 @@ predicate semImplies_v2(SemGuard g1, boolean b1, SemGuard g2, boolean b2) {
Specific::implies_v2(g1, b1, g2, b2)
}
/**
* Holds if `guard` directly controls the position `controlled` with the
* value `testIsTrue`.
*/
pragma[nomagic]
predicate semGuardDirectlyControlsSsaRead(
SemGuard guard, SemSsaReadPosition controlled, boolean testIsTrue
) {
guard.directlyControls(controlled.(SemSsaReadPositionBlock).getBlock(), testIsTrue)
or
exists(SemSsaReadPositionPhiInputEdge controlledEdge | controlledEdge = controlled |
guard.directlyControls(controlledEdge.getOrigBlock(), testIsTrue) or
guard.hasBranchEdge(controlledEdge.getOrigBlock(), controlledEdge.getPhiBlock(), testIsTrue)
)
}
/**
* Holds if `guard` controls the position `controlled` with the value `testIsTrue`.
*/
predicate semGuardControlsSsaRead(SemGuard guard, SemSsaReadPosition controlled, boolean testIsTrue) {
semGuardDirectlyControlsSsaRead(guard, controlled, testIsTrue)
or
exists(SemGuard guard0, boolean testIsTrue0 |
semImplies_v2(guard0, testIsTrue0, guard, testIsTrue) and
semGuardControlsSsaRead(guard0, controlled, testIsTrue0)
)
}
SemGuard semGetComparisonGuard(SemRelationalExpr e) { result = Specific::comparisonGuard(e) }

View File

@@ -78,10 +78,6 @@ module Sem implements Semantic {
predicate implies_v2 = semImplies_v2/4;
predicate guardDirectlyControlsSsaRead = semGuardDirectlyControlsSsaRead/3;
predicate guardControlsSsaRead = semGuardControlsSsaRead/3;
class Type = SemType;
class IntegerType = SemIntegerType;

View File

@@ -294,7 +294,7 @@ module SignAnalysis<DeltaSig D, UtilSig<Sem, D> Utils> {
) {
exists(boolean testIsTrue, SemRelationalExpr comp |
pos.hasReadOfVar(v) and
semGuardControlsSsaRead(semGetComparisonGuard(comp), pos, testIsTrue) and
guardControlsSsaRead(semGetComparisonGuard(comp), pos, testIsTrue) and
not unknownSign(lowerbound)
|
testIsTrue = true and
@@ -318,7 +318,7 @@ module SignAnalysis<DeltaSig D, UtilSig<Sem, D> Utils> {
) {
exists(boolean testIsTrue, SemRelationalExpr comp |
pos.hasReadOfVar(v) and
semGuardControlsSsaRead(semGetComparisonGuard(comp), pos, testIsTrue) and
guardControlsSsaRead(semGetComparisonGuard(comp), pos, testIsTrue) and
not unknownSign(upperbound)
|
testIsTrue = true and
@@ -343,7 +343,7 @@ module SignAnalysis<DeltaSig D, UtilSig<Sem, D> Utils> {
private predicate eqBound(SemExpr eqbound, SemSsaVariable v, SemSsaReadPosition pos, boolean isEq) {
exists(SemGuard guard, boolean testIsTrue, boolean polarity, SemExpr e |
pos.hasReadOfVar(pragma[only_bind_into](v)) and
semGuardControlsSsaRead(guard, pragma[only_bind_into](pos), testIsTrue) and
guardControlsSsaRead(guard, pragma[only_bind_into](pos), testIsTrue) and
e = ssaRead(pragma[only_bind_into](v), D::fromInt(0)) and
guard.isEquality(eqbound, e, polarity) and
isEq = polarity.booleanXor(testIsTrue).booleanNot() and

View File

@@ -223,14 +223,6 @@ module Sem implements Semantic {
GL::implies_v2(g1, b1, g2, b2)
}
predicate guardDirectlyControlsSsaRead(Guard guard, SsaReadPosition controlled, boolean testIsTrue) {
RU::guardDirectlyControlsSsaRead(guard, controlled, testIsTrue)
}
predicate guardControlsSsaRead(Guard guard, SsaReadPosition controlled, boolean testIsTrue) {
RU::guardControlsSsaRead(guard, controlled, testIsTrue)
}
class Type = J::Type;
class IntegerType extends J::IntegralType {
@@ -267,6 +259,8 @@ module Sem implements Semantic {
{
BasicBlock getOrigBlock() { result = super.getOrigBlock() }
BasicBlock getPhiBlock() { result = super.getPhiBlock() }
predicate phiInput(SsaPhiNode phi, SsaVariable inp) { super.phiInput(phi, inp) }
}

View File

@@ -10,7 +10,15 @@ private import semmle.code.java.Constants
private import semmle.code.java.dataflow.RangeAnalysis
private import codeql.rangeanalysis.internal.RangeUtils
private predicate backEdge = MakeUtils<Sem, IntDelta>::backEdge/3;
private module U = MakeUtils<Sem, IntDelta>;
private predicate backEdge = U::backEdge/3;
predicate ssaRead = U::ssaRead/2;
predicate guardDirectlyControlsSsaRead = U::guardDirectlyControlsSsaRead/3;
predicate guardControlsSsaRead = U::guardControlsSsaRead/3;
/**
* Holds if `v` is an input to `phi` that is not along a back edge, and the
@@ -149,67 +157,6 @@ class ConstantStringExpr extends Expr {
string getStringValue() { constantStringExpr(this, result) }
}
bindingset[f]
private predicate okInt(float f) { -2.pow(31) <= f and f <= 2.pow(31) - 1 }
/**
* Gets an expression that equals `v - d`.
*/
Expr ssaRead(SsaVariable v, int delta) {
result = v.getAUse() and delta = 0
or
exists(int d1, ConstantIntegerExpr c |
result.(AddExpr).hasOperands(ssaRead(v, d1), c) and
delta = d1 - c.getIntValue() and
okInt(d1.(float) - c.getIntValue().(float))
)
or
exists(SubExpr sub, int d1, ConstantIntegerExpr c |
result = sub and
sub.getLeftOperand() = ssaRead(v, d1) and
sub.getRightOperand() = c and
delta = d1 + c.getIntValue() and
okInt(d1.(float) + c.getIntValue().(float))
)
or
v.(SsaExplicitUpdate).getDefiningExpr().(PreIncExpr) = result and delta = 0
or
v.(SsaExplicitUpdate).getDefiningExpr().(PreDecExpr) = result and delta = 0
or
v.(SsaExplicitUpdate).getDefiningExpr().(PostIncExpr) = result and delta = 1 // x++ === ++x - 1
or
v.(SsaExplicitUpdate).getDefiningExpr().(PostDecExpr) = result and delta = -1 // x-- === --x + 1
or
v.(SsaExplicitUpdate).getDefiningExpr().(Assignment) = result and delta = 0
or
result.(AssignExpr).getSource() = ssaRead(v, delta)
}
/**
* Holds if `guard` directly controls the position `controlled` with the
* value `testIsTrue`.
*/
predicate guardDirectlyControlsSsaRead(Guard guard, SsaReadPosition controlled, boolean testIsTrue) {
guard.directlyControls(controlled.(SsaReadPositionBlock).getBlock(), testIsTrue)
or
exists(SsaReadPositionPhiInputEdge controlledEdge | controlledEdge = controlled |
guard.directlyControls(controlledEdge.getOrigBlock(), testIsTrue) or
guard.hasBranchEdge(controlledEdge.getOrigBlock(), controlledEdge.getPhiBlock(), testIsTrue)
)
}
/**
* Holds if `guard` controls the position `controlled` with the value `testIsTrue`.
*/
predicate guardControlsSsaRead(Guard guard, SsaReadPosition controlled, boolean testIsTrue) {
guardDirectlyControlsSsaRead(guard, controlled, testIsTrue)
or
exists(Guard guard0, boolean testIsTrue0 |
implies_v2(guard0, testIsTrue0, guard, testIsTrue) and
guardControlsSsaRead(guard0, controlled, testIsTrue0)
)
}
/**
* Gets a condition that tests whether `v` equals `e + delta`.
*

View File

@@ -17,6 +17,8 @@ module ModulusAnalysis<
LocationSig Location, Semantic Sem, DeltaSig D, BoundSig<Location, Sem, D> Bounds,
UtilSig<Sem, D> U>
{
private import internal.RangeUtils::MakeUtils<Sem, D>
bindingset[pos, v]
pragma[inline_late]
private predicate hasReadOfVarInlineLate(Sem::SsaReadPosition pos, Sem::SsaVariable v) {
@@ -35,7 +37,7 @@ module ModulusAnalysis<
exists(Sem::Guard guard, boolean testIsTrue |
hasReadOfVarInlineLate(pos, v) and
guard = U::semEqFlowCond(v, e, D::fromInt(delta), true, testIsTrue) and
Sem::guardDirectlyControlsSsaRead(guard, pos, testIsTrue)
guardDirectlyControlsSsaRead(guard, pos, testIsTrue)
)
}
@@ -107,7 +109,7 @@ module ModulusAnalysis<
exists(Sem::Guard guard, boolean testIsTrue |
pos.hasReadOfVar(v) and
guard = moduloCheck(v, val, mod, testIsTrue) and
Sem::guardControlsSsaRead(guard, pos, testIsTrue)
guardControlsSsaRead(guard, pos, testIsTrue)
)
}

View File

@@ -160,14 +160,12 @@ signature module Semantic {
predicate directlyControls(BasicBlock controlled, boolean branch);
predicate isEquality(Expr e1, Expr e2, boolean polarity);
predicate hasBranchEdge(BasicBlock bb1, BasicBlock bb2, boolean branch);
}
predicate implies_v2(Guard g1, boolean b1, Guard g2, boolean b2);
predicate guardDirectlyControlsSsaRead(Guard guard, SsaReadPosition controlled, boolean testIsTrue);
predicate guardControlsSsaRead(Guard guard, SsaReadPosition controlled, boolean testIsTrue);
class Type;
class IntegerType extends Type {
@@ -199,6 +197,8 @@ signature module Semantic {
class SsaReadPositionPhiInputEdge extends SsaReadPosition {
BasicBlock getOrigBlock();
BasicBlock getPhiBlock();
predicate phiInput(SsaPhiNode phi, SsaVariable inp);
}
@@ -699,7 +699,7 @@ module RangeStage<
exists(Sem::Guard guard, boolean testIsTrue |
pos.hasReadOfVar(v) and
guard = boundFlowCond(v, e, delta, upper, testIsTrue) and
Sem::guardDirectlyControlsSsaRead(guard, pos, testIsTrue) and
guardDirectlyControlsSsaRead(guard, pos, testIsTrue) and
reason = TSemCondReason(guard)
)
}
@@ -712,7 +712,7 @@ module RangeStage<
exists(Sem::Guard guard, boolean testIsTrue |
pos.hasReadOfVar(v) and
guard = semEqFlowCond(v, e, delta, false, testIsTrue) and
Sem::guardDirectlyControlsSsaRead(guard, pos, testIsTrue) and
guardDirectlyControlsSsaRead(guard, pos, testIsTrue) and
reason = TSemCondReason(guard)
)
}

View File

@@ -35,6 +35,32 @@ module MakeUtils<Semantic Lang, DeltaSig D> {
result.(Lang::CopyValueExpr).getOperand() = ssaRead(v, delta)
}
/**
* Holds if `guard` directly controls the position `controlled` with the
* value `testIsTrue`.
*/
pragma[nomagic]
predicate guardDirectlyControlsSsaRead(Lang::Guard guard, Lang::SsaReadPosition controlled, boolean testIsTrue) {
guard.directlyControls(controlled.(Lang::SsaReadPositionBlock).getBlock(), testIsTrue)
or
exists(Lang::SsaReadPositionPhiInputEdge controlledEdge | controlledEdge = controlled |
guard.directlyControls(controlledEdge.getOrigBlock(), testIsTrue) or
guard.hasBranchEdge(controlledEdge.getOrigBlock(), controlledEdge.getPhiBlock(), testIsTrue)
)
}
/**
* Holds if `guard` controls the position `controlled` with the value `testIsTrue`.
*/
predicate guardControlsSsaRead(Lang::Guard guard, Lang::SsaReadPosition controlled, boolean testIsTrue) {
guardDirectlyControlsSsaRead(guard, controlled, testIsTrue)
or
exists(Lang::Guard guard0, boolean testIsTrue0 |
Lang::implies_v2(guard0, testIsTrue0, guard, testIsTrue) and
guardControlsSsaRead(guard0, controlled, testIsTrue0)
)
}
/**
* Holds if `inp` is an input to `phi` along a back edge.
*/