Add ConstantLShiftExprRange and ConstantRShiftExprRange classes

This commit is contained in:
Gulshan Singh
2023-01-18 00:31:45 -08:00
committed by Gulshan Singh
parent 5710289460
commit 051d36ee6a
4 changed files with 308 additions and 18 deletions

View File

@@ -0,0 +1,152 @@
private import cpp
private import experimental.semmle.code.cpp.models.interfaces.SimpleRangeAnalysisExpr
private import semmle.code.cpp.rangeanalysis.RangeAnalysisUtils
float evaluateConstantExpr2(Expr e) {
result = e.getValue().toFloat()
or
// This handles when a constant value is put into a variable
// and the variable is used later
exists(SsaDefinition defn, StackVariable sv |
defn.getAUse(sv) = e and
result = defn.getDefiningValue(sv).getValue().toFloat()
)
}
// If the constant right operand is negative or is greater than or equal to the number of
// bits in the left operands type, then the result is undefined (except on the IA-32
// architecture where the shift value is masked with 0b00011111, but we can't
// assume the architecture).
bindingset[val]
pragma[inline]
private predicate isValidShiftExprShift(float val, Expr l) {
val >= 0 and
// We use getFullyConverted because the spec says to use the *promoted* left operand
val < (l.getFullyConverted().getUnderlyingType().getSize() * 8)
}
bindingset[val, shift, max_val]
private predicate canLShiftOverflow(int val, int shift, int max_val) {
// val << shift = val * 2^shift > max_val => val > max_val/2^shift = max_val >> b
val > max_val.bitShiftRight(shift)
}
/**
* This handles the `<<` and `<<=` operators when at least one operand is a constant (and if the right operand
* is a constant, it must be "valid" (see `isValidShiftExprShift`)). When handling any undefined behavior, it
* leaves the values unconstrained. From the C++ standard: "The behavior is undefined if the right
* operand is negative, or greater than or equal to the length in bits of the promoted left operand.
* The value of E1 << E2 is E1 left-shifted E2 bit positions; vacated bits are zero-filled. If E1
* has an unsigned type, the value of the result is E1 × 2 E2, reduced modulo one more than the
* maximum value representable in the result type. Otherwise, if E1 has a signed type and
* non-negative value, and E1 × 2 E2 is representable in the corresponding unsigned type of the
* result type, then that value, converted to the result type, is the resulting value; otherwise,
* the behavior is undefined."
*/
class ConstantLShiftExprRange extends SimpleRangeAnalysisExpr {
/**
* Holds for `a << b` or `a <<= b` in one of the following two cases:
* 1. `a` is a constant and `b` is not
* 2. `b` is constant
*
* We don't handle the case where `a` and `b` are both non-constant values.
*/
ConstantLShiftExprRange() {
getUnspecifiedType() instanceof IntegralType and
exists(Expr l, Expr r |
l = this.(LShiftExpr).getLeftOperand() and
r = this.(LShiftExpr).getRightOperand()
or
l = this.(AssignLShiftExpr).getLValue() and
r = this.(AssignLShiftExpr).getRValue()
|
l.getUnspecifiedType() instanceof IntegralType and
r.getUnspecifiedType() instanceof IntegralType and
(
// If the left operand is a constant, verify that the right operand is not a constant
exists(evaluateConstantExpr2(l)) and not exists(evaluateConstantExpr2(r))
or
// If the right operand is a constant, check if it is a valid shift expression
exists(float constROp |
constROp = evaluateConstantExpr2(r) and isValidShiftExprShift(constROp, l)
)
)
)
}
Expr getLeftOperand() {
result = this.(LShiftExpr).getLeftOperand() or
result = this.(AssignLShiftExpr).getLValue()
}
Expr getRightOperand() {
result = this.(LShiftExpr).getRightOperand() or
result = this.(AssignLShiftExpr).getRValue()
}
override float getLowerBounds() {
exists(int lLower, int lUpper, int rLower, int rUpper |
lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
lUpper = getFullyConvertedUpperBounds(getLeftOperand()) and
rLower = getFullyConvertedLowerBounds(getRightOperand()) and
rUpper = getFullyConvertedUpperBounds(getRightOperand()) and
lLower <= lUpper and
rLower <= rUpper
|
if
lLower < 0
or
not (
isValidShiftExprShift(rLower, getLeftOperand()) and
isValidShiftExprShift(rUpper, getLeftOperand())
)
then
// We don't want to deal with shifting negative numbers at the moment,
// and a negative shift is undefined, so we set to the minimum value
result = exprMinVal(this)
else
// If we have `0b01010000 << [0, 2]`, the max value for 8 bits is 0b10100000
// (a shift of 1) but doing a shift by the upper bound would give 0b01000000.
// So if the left shift operation causes an overflow, we just assume the max value
// If necessary, we may be able to improve this bound in the future
if canLShiftOverflow(lUpper, rUpper, exprMaxVal(this).(int))
then result = exprMinVal(this)
else result = lLower.bitShiftLeft(rLower)
)
}
override float getUpperBounds() {
exists(int lLower, int lUpper, int rLower, int rUpper |
lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
lUpper = getFullyConvertedUpperBounds(getLeftOperand()) and
rLower = getFullyConvertedLowerBounds(getRightOperand()) and
rUpper = getFullyConvertedUpperBounds(getRightOperand()) and
lLower <= lUpper and
rLower <= rUpper
|
if
lLower < 0
or
not (
isValidShiftExprShift(rLower, getLeftOperand()) and
isValidShiftExprShift(rUpper, getLeftOperand())
)
then
// We don't want to deal with shifting negative numbers at the moment,
// and a negative shift is undefined, so we set it to the maximum value
result = exprMaxVal(this)
else
// If we have `0b01010000 << [0, 2]`, the max value for 8 bits is 0b10100000
// (a shift of 1) but doing a shift by the upper bound would give 0b01000000.
// So if the left shift operation causes an overflow, we just assume the max value
// If necessary, we may be able to improve this bound in the future
if canLShiftOverflow(lUpper, rUpper, exprMaxVal(this).(int))
then result = exprMaxVal(this)
else result = lUpper.bitShiftLeft(rUpper)
)
}
override predicate dependsOnChild(Expr child) {
child = getLeftOperand() or child = getLeftOperand()
}
}

View File

@@ -0,0 +1,136 @@
private import cpp
private import experimental.semmle.code.cpp.models.interfaces.SimpleRangeAnalysisExpr
private import semmle.code.cpp.rangeanalysis.RangeAnalysisUtils
float evaluateConstantExpr1(Expr e) {
result = e.getValue().toFloat()
or
// This handles when a constant value is put into a variable
// and the variable is used later
exists(SsaDefinition defn, StackVariable sv |
defn.getAUse(sv) = e and
result = defn.getDefiningValue(sv).getValue().toFloat()
)
}
// If the constant right operand is negative or is greater than or equal to the number of
// bits in the left operands type, then the result is undefined (except on the IA-32
// architecture where the shift value is masked with 0b00011111, but we can't
// assume the architecture).
bindingset[val]
pragma[inline]
private predicate isValidShiftExprShift(float val, Expr l) {
val >= 0 and
// We use getFullyConverted because the spec says to use the *promoted* left operand
val < (l.getFullyConverted().getUnderlyingType().getSize() * 8)
}
/**
* This handles the `>>` and `>>=` operators when at least one operand is a constant (and if the
* right operand is a constant, it must be "valid" (see `isValidShiftExprShift`)). When handling any
* undefined behavior, it leaves the values unconstrained. From the C++ standard: "The behavior is
* undefined if the right operand is negative, or greater than or equal to the length in bits of the
* promoted left operand. The value of E1 >> E2 is E1 right-shifted E2 bit positions. If E1 has an
* unsigned type or if E1 has a signed type and a non-negative value, the value of the result is the
* integral part of the quotient of E1/2^E2. If E1 has a signed type and a negative value, the
* resulting value is implementation-defined."
*/
class ConstantRShiftExprRange extends SimpleRangeAnalysisExpr {
/**
* Holds for `a >> b` or `a >>= b` in one of the following two cases:
* 1. `a` is a constant and `b` is not
* 2. `b` is constant
*
* We don't handle the case where `a` and `b` are both non-constant values.
*/
ConstantRShiftExprRange() {
getUnspecifiedType() instanceof IntegralType and
exists(Expr l, Expr r |
l = this.(RShiftExpr).getLeftOperand() and
r = this.(RShiftExpr).getRightOperand()
or
l = this.(AssignRShiftExpr).getLValue() and
r = this.(AssignRShiftExpr).getRValue()
|
l.getUnspecifiedType() instanceof IntegralType and
r.getUnspecifiedType() instanceof IntegralType and
(
// If the left operand is a constant, verify that the right operand is not a constant
exists(evaluateConstantExpr1(l)) and not exists(evaluateConstantExpr1(r))
or
// If the right operand is a constant, check if it is a valid shift expression
exists(float constROp |
constROp = evaluateConstantExpr1(r) and isValidShiftExprShift(constROp, l)
)
)
)
}
Expr getLeftOperand() {
result = this.(RShiftExpr).getLeftOperand() or
result = this.(AssignRShiftExpr).getLValue()
}
Expr getRightOperand() {
result = this.(RShiftExpr).getRightOperand() or
result = this.(AssignRShiftExpr).getRValue()
}
override float getLowerBounds() {
exists(int lLower, int lUpper, int rLower, int rUpper |
lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
lUpper = getFullyConvertedUpperBounds(getLeftOperand()) and
rLower = getFullyConvertedLowerBounds(getRightOperand()) and
rUpper = getFullyConvertedUpperBounds(getRightOperand()) and
lLower <= lUpper and
rLower <= rUpper
|
if
lLower < 0
or
not (
isValidShiftExprShift(rLower, getLeftOperand()) and
isValidShiftExprShift(rUpper, getLeftOperand())
)
then
// We don't want to deal with shifting negative numbers at the moment,
// and a negative shift is implementation defined, so we set the result
// to the minimum value
result = exprMinVal(this)
else
// We can get the smallest value by shifting the smallest bound by the largest bound
result = lLower.bitShiftRight(rUpper)
)
}
override float getUpperBounds() {
exists(int lLower, int lUpper, int rLower, int rUpper |
lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
lUpper = getFullyConvertedUpperBounds(getLeftOperand()) and
rLower = getFullyConvertedLowerBounds(getRightOperand()) and
rUpper = getFullyConvertedUpperBounds(getRightOperand()) and
lLower <= lUpper and
rLower <= rUpper
|
if
lLower < 0
or
not (
isValidShiftExprShift(rLower, getLeftOperand()) and
isValidShiftExprShift(rUpper, getLeftOperand())
)
then
// We don't want to deal with shifting negative numbers at the moment,
// and a negative shift is implementation defined, so we set the result
// to the maximum value
result = exprMaxVal(this)
else
// We can get the largest value by shifting the largest bound by the smallest bound
result = lUpper.bitShiftRight(rLower)
)
}
override predicate dependsOnChild(Expr child) {
child = getLeftOperand() or child = getLeftOperand()
}
}

View File

@@ -1,15 +1,15 @@
| bitshift.cpp:23:3:23:9 | ... <<= ... | 0.0 | 255.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int |
| bitshift.cpp:25:5:25:11 | ... <<= ... | 0.0 | 255.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int |
| bitshift.cpp:29:3:29:8 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:25:5:25:11 | ... <<= ... | 0.0 | 240.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int |
| bitshift.cpp:29:3:29:8 | ... << ... | 0.0 | 1020.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:32:3:32:9 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:35:3:35:9 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:38:3:38:22 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:39:3:39:22 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:40:3:40:22 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:38:3:38:22 | ... << ... | 0.0 | 32640.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:39:3:39:22 | ... << ... | 0.0 | 32640.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:40:3:40:22 | ... << ... | 0.0 | 32640.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:43:3:43:19 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:46:3:46:22 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:46:3:46:22 | ... << ... | 128.0 | 128.0 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:49:3:49:8 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:52:5:52:10 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:52:5:52:10 | ... << ... | 1.0 | 128.0 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:57:3:57:8 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:58:3:58:9 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:59:3:59:9 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
@@ -17,28 +17,28 @@
| bitshift.cpp:61:3:61:19 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:64:3:64:19 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:67:3:67:8 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:70:5:70:10 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:70:5:70:10 | ... << ... | 1.0 | 128.0 | file://:0:0:0:0 | int | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:75:5:75:10 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:76:5:76:10 | ... << ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:90:3:90:9 | ... >>= ... | 0.0 | 255.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int |
| bitshift.cpp:92:5:92:11 | ... >>= ... | 0.0 | 255.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int |
| bitshift.cpp:90:3:90:9 | ... >>= ... | 0.0 | 63.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int |
| bitshift.cpp:92:5:92:11 | ... >>= ... | 0.0 | 15.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int |
| bitshift.cpp:96:3:96:8 | ... >> ... | 0.0 | 63.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:99:3:99:9 | ... >> ... | 0.0 | 0.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:103:3:103:9 | ... >> ... | 0.0 | 0.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:106:3:106:22 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:107:3:107:22 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:108:3:108:22 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:106:3:106:22 | ... >> ... | 0.0 | 63.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:107:3:107:22 | ... >> ... | 0.0 | 63.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:108:3:108:22 | ... >> ... | 0.0 | 63.0 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:111:3:111:19 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:114:3:114:24 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:114:3:114:24 | ... >> ... | 32.0 | 32.0 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:117:3:117:10 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:120:5:120:12 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:126:3:126:8 | ... >> ... | -32.0 | 31.0 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:127:3:127:9 | ... >> ... | -1.0 | 0.0 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:120:5:120:12 | ... >> ... | 32.0 | 128.0 | file://:0:0:0:0 | int | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:126:3:126:8 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:127:3:127:9 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:128:3:128:9 | ... >> ... | -1.0 | 0.0 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:129:3:129:22 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:130:3:130:19 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:133:3:133:21 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:136:3:136:10 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:139:5:139:12 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | int | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:139:5:139:12 | ... >> ... | 32.0 | 128.0 | file://:0:0:0:0 | int | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:144:5:144:10 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | signed char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
| bitshift.cpp:145:5:145:10 | ... >> ... | -2.147483648E9 | 2.147483647E9 | file://:0:0:0:0 | signed char | file://:0:0:0:0 | unsigned char | file://:0:0:0:0 | int | file://:0:0:0:0 | int |

View File

@@ -1,5 +1,7 @@
import cpp
import semmle.code.cpp.rangeanalysis.SimpleRangeAnalysis
import experimental.semmle.code.cpp.rangeanalysis.extensions.ConstantLShiftExprRange
import experimental.semmle.code.cpp.rangeanalysis.extensions.ConstantRShiftExprRange
Expr getLOp(Operation o) {
result = o.(BinaryOperation).getLeftOperand() or