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MathisGDMathisGD
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Merge pull request #106 from morpho-org/test/abs-certora
Add Certora verification for `abs` and `safeAbs`
2 parents 540207b + 82669d7 commit d50e424

8 files changed

Lines changed: 103 additions & 59 deletions

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‎certora/scripts/verifyAll.sh‎

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set -euxo pipefail
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certora/scripts/verifyBitvectorMath.sh $@
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certora/scripts/verifyCompoundMath.sh $@
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certora/scripts/verifyMath.sh $@
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certora/scripts/verifyPercentageMath.sh $@

‎certora/scripts/verifyBitvectorMath.sh‎

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#!/bin/bash
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certoraRun \
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test/mocks/MathMock.sol \
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--verify MathMock:certora/specs/bitvectorMath.spec \
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--settings -useBitVectorTheory \
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--msg "Math" \
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$@

‎certora/scripts/verifyMath.sh‎

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certoraRun \
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test/mocks/MathMock.sol \
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--verify MathMock:certora/specs/math.spec \
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--settings -useBitVectorTheory \
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--msg "Math" \
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$@
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‎certora/specs/bitvectorMath.spec‎

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methods {
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function min(uint256, uint256) external returns (uint256) envfree;
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function max(uint256, uint256) external returns (uint256) envfree;
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}
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/// min ///
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rule minSafety(uint256 a, uint256 b) {
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uint res = min(a, b);
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assert a <= b => res == a;
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assert a > b => res == b;
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}
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rule minLiveness(uint256 a, uint256 b) {
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min@withrevert(a, b);
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assert lastReverted <=> false;
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}
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/// max ///
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rule maxSafety(uint256 a, uint256 b) {
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uint res = max(a, b);
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assert a >= b => res == a;
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assert a < b => res == b;
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}
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rule maxLiveness(uint256 a, uint256 b) {
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max@withrevert(a, b);
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assert lastReverted <=> false;
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}

‎certora/specs/compoundMath.spec‎

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methods {
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function mul(uint256, uint256) external returns (uint256) envfree;
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function div(uint256, uint256) external returns (uint256) envfree;
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function mul(uint256, uint256) external returns (uint256) envfree;
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function div(uint256, uint256) external returns (uint256) envfree;
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}
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definition WAD() returns uint = 10^18;
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definition WAD() returns uint = 10^18;
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definition UINT_LIMIT() returns mathint = 2 ^ 255 * 2;
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/// mul ///

‎certora/specs/math.spec‎

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methods {
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function min(uint256, uint256) external returns (uint256) envfree;
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function max(uint256, uint256) external returns (uint256) envfree;
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function zeroFloorSub(uint256, uint256) external returns (uint256) envfree;
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function divUp(uint256, uint256) external returns (uint256) envfree;
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function abs(int256) external returns (int256) envfree;
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function safeAbs(int256) external returns (int256) envfree;
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function zeroFloorSub(uint256, uint256) external returns (uint256) envfree;
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function divUp(uint256, uint256) external returns (uint256) envfree;
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}
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/// min ///
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definition MIN_INT256() returns int256 = -2^255;
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definition MAX_INT256() returns int256 = 2^255 - 1;
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/// abs ///
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rule minSafety(uint256 a, uint256 b) {
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uint res = min(a, b);
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rule absSafety(int256 a) {
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int256 res = abs(a);
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assert a <= b => res == a;
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assert a > b => res == b;
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assert a >= 0 => res == a;
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assert a < 0 && a > MIN_INT256() => to_mathint(res) == -a;
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assert a == MIN_INT256() => res == MAX_INT256();
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}
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rule minLiveness(uint256 a, uint256 b) {
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min@withrevert(a, b);
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rule absLiveness(int256 a) {
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abs@withrevert(a);
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assert lastReverted <=> false;
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}
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/// max ///
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/// safeAbs ///
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rule maxSafety(uint256 a, uint256 b) {
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uint res = max(a, b);
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rule safeAbsSafety(int256 a) {
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int256 res = safeAbs(a);
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assert a >= b => res == a;
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assert a < b => res == b;
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assert a >= 0 => res == a;
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assert a < 0 => to_mathint(res) == -a;
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}
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rule maxLiveness(uint256 a, uint256 b) {
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max@withrevert(a, b);
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rule safeAbsLiveness(int256 a) {
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safeAbs@withrevert(a);
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assert lastReverted <=> false;
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assert lastReverted <=> a == MIN_INT256();
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}
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/// zeroFloorSub ///
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rule zeroFloorSubSafety(uint256 a, uint256 b) {

‎certora/specs/percentageMath.spec‎

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methods {
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function percentAdd(uint256, uint256) external returns (uint256) envfree;
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function percentSub(uint256, uint256) external returns (uint256) envfree;
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function percentMul(uint256, uint256) external returns (uint256) envfree;
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function percentMulDown(uint256, uint256) external returns (uint256) envfree;
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function percentMulUp(uint256, uint256) external returns (uint256) envfree;
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function percentDiv(uint256, uint256) external returns (uint256) envfree;
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function percentDivDown(uint256, uint256) external returns (uint256) envfree;
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function percentDivUp(uint256, uint256) external returns (uint256) envfree;
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function weightedAvg(uint256, uint256, uint256) external returns (uint256) envfree;
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}
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definition PERCENTAGE_FACTOR() returns uint = 10^4;
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function percentAdd(uint256, uint256) external returns (uint256) envfree;
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function percentSub(uint256, uint256) external returns (uint256) envfree;
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function percentMul(uint256, uint256) external returns (uint256) envfree;
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function percentMulDown(uint256, uint256) external returns (uint256) envfree;
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function percentMulUp(uint256, uint256) external returns (uint256) envfree;
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function percentDiv(uint256, uint256) external returns (uint256) envfree;
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function percentDivDown(uint256, uint256) external returns (uint256) envfree;
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function percentDivUp(uint256, uint256) external returns (uint256) envfree;
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function weightedAvg(uint256, uint256, uint256) external returns (uint256) envfree;
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}
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definition PERCENTAGE_FACTOR() returns uint = 10^4;
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definition UINT_LIMIT() returns mathint = 2 ^ 255 * 2;
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/// percentAdd ///

‎certora/specs/wadRayMath.spec‎

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methods {
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function wadMul(uint256, uint256) external returns (uint256) envfree;
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function wadMulDown(uint256, uint256) external returns (uint256) envfree;
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function wadMulUp(uint256, uint256) external returns (uint256) envfree;
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function wadDiv(uint256, uint256) external returns (uint256) envfree;
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function wadDivDown(uint256, uint256) external returns (uint256) envfree;
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function wadDivUp(uint256, uint256) external returns (uint256) envfree;
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function rayMul(uint256, uint256) external returns (uint256) envfree;
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function rayMulDown(uint256, uint256) external returns (uint256) envfree;
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function rayMulUp(uint256, uint256) external returns (uint256) envfree;
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function rayDiv(uint256, uint256) external returns (uint256) envfree;
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function rayDivDown(uint256, uint256) external returns (uint256) envfree;
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function rayDivUp(uint256, uint256) external returns (uint256) envfree;
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function rayToWad(uint256) external returns (uint256) envfree;
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function wadToRay(uint256) external returns (uint256) envfree;
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function wadWeightedAvg(uint256, uint256, uint256) external returns (uint256) envfree;
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function rayWeightedAvg(uint256, uint256, uint256) external returns (uint256) envfree;
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}
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definition WAD() returns uint = 10^18;
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definition RAY() returns uint = 10^27;
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definition WADTORAY() returns uint = 10^9;
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function wadMul(uint256, uint256) external returns (uint256) envfree;
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function wadMulDown(uint256, uint256) external returns (uint256) envfree;
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function wadMulUp(uint256, uint256) external returns (uint256) envfree;
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function wadDiv(uint256, uint256) external returns (uint256) envfree;
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function wadDivDown(uint256, uint256) external returns (uint256) envfree;
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function wadDivUp(uint256, uint256) external returns (uint256) envfree;
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function rayMul(uint256, uint256) external returns (uint256) envfree;
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function rayMulDown(uint256, uint256) external returns (uint256) envfree;
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function rayMulUp(uint256, uint256) external returns (uint256) envfree;
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function rayDiv(uint256, uint256) external returns (uint256) envfree;
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function rayDivDown(uint256, uint256) external returns (uint256) envfree;
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function rayDivUp(uint256, uint256) external returns (uint256) envfree;
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function rayToWad(uint256) external returns (uint256) envfree;
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function wadToRay(uint256) external returns (uint256) envfree;
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function wadWeightedAvg(uint256, uint256, uint256) external returns (uint256) envfree;
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function rayWeightedAvg(uint256, uint256, uint256) external returns (uint256) envfree;
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}
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definition WAD() returns uint = 10^18;
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definition RAY() returns uint = 10^27;
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definition WADTORAY() returns uint = 10^9;
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definition UINT_LIMIT() returns mathint = 2 ^ 255 * 2;
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/// wadMul ///

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