diff options
Diffstat (limited to 'test/Analysis/idempotent-operations.c')
| -rw-r--r-- | test/Analysis/idempotent-operations.c | 203 |
1 files changed, 170 insertions, 33 deletions
diff --git a/test/Analysis/idempotent-operations.c b/test/Analysis/idempotent-operations.c index 9cef08e..5c9a59d 100644 --- a/test/Analysis/idempotent-operations.c +++ b/test/Analysis/idempotent-operations.c @@ -1,52 +1,189 @@ -// RUN: %clang_cc1 -analyze -analyzer-idempotent-operation -analyzer-store=region -analyzer-constraints=range -fblocks -verify -analyzer-opt-analyze-nested-blocks -analyzer-check-objc-mem -verify %s +// RUN: %clang_cc1 -analyze -analyzer-store=region -analyzer-constraints=range -fblocks -analyzer-opt-analyze-nested-blocks -analyzer-check-objc-mem -analyzer-check-idempotent-operations -verify %s // Basic tests extern void test(int i); +extern void test_f(float f); -void basic() { +unsigned basic() { int x = 10, zero = 0, one = 1; // x op x - x = x; // expected-warning {{idempotent operation; both operands are always equal in value}} - test(x - x); // expected-warning {{idempotent operation; both operands are always equal in value}} - x -= x; // expected-warning {{idempotent operation; both operands are always equal in value}} + x = x; // expected-warning {{Assigned value is always the same as the existing value}} + test(x - x); // expected-warning {{Both operands to '-' always have the same value}} + x -= x; // expected-warning {{Both operands to '-=' always have the same value}} x = 10; // no-warning - test(x / x); // expected-warning {{idempotent operation; both operands are always equal in value}} - x /= x; // expected-warning {{idempotent operation; both operands are always equal in value}} + test(x / x); // expected-warning {{Both operands to '/' always have the same value}} + x /= x; // expected-warning {{Both operands to '/=' always have the same value}} x = 10; // no-warning - test(x & x); // expected-warning {{idempotent operation; both operands are always equal in value}} - x &= x; // expected-warning {{idempotent operation; both operands are always equal in value}} - test(x | x); // expected-warning {{idempotent operation; both operands are always equal in value}} - x |= x; // expected-warning {{idempotent operation; both operands are always equal in value}} + test(x & x); // expected-warning {{Both operands to '&' always have the same value}} + x &= x; // expected-warning {{Both operands to '&=' always have the same value}} + test(x | x); // expected-warning {{Both operands to '|' always have the same value}} + x |= x; // expected-warning {{Both operands to '|=' always have the same value}} // x op 1 - test(x * one); // expected-warning {{idempotent operation; the right operand is always 1}} - x *= one; // expected-warning {{idempotent operation; the right operand is always 1}} - test(x / one); // expected-warning {{idempotent operation; the right operand is always 1}} - x /= one; // expected-warning {{idempotent operation; the right operand is always 1}} + test(x * one); // expected-warning {{The right operand to '*' is always 1}} + x *= one; // expected-warning {{The right operand to '*=' is always 1}} + test(x / one); // expected-warning {{The right operand to '/' is always 1}} + x /= one; // expected-warning {{The right operand to '/=' is always 1}} // 1 op x - test(one * x); // expected-warning {{idempotent operation; the left operand is always 1}} + test(one * x); // expected-warning {{The left operand to '*' is always 1}} // x op 0 - test(x + zero); // expected-warning {{idempotent operation; the right operand is always 0}} - test(x - zero); // expected-warning {{idempotent operation; the right operand is always 0}} - test(x * zero); // expected-warning {{idempotent operation; the right operand is always 0}} - test(x & zero); // expected-warning {{idempotent operation; the right operand is always 0}} - test(x | zero); // expected-warning {{idempotent operation; the right operand is always 0}} - test(x ^ zero); // expected-warning {{idempotent operation; the right operand is always 0}} - test(x << zero); // expected-warning {{idempotent operation; the right operand is always 0}} - test(x >> zero); // expected-warning {{idempotent operation; the right operand is always 0}} + test(x + zero); // expected-warning {{The right operand to '+' is always 0}} + test(x - zero); // expected-warning {{The right operand to '-' is always 0}} + test(x * zero); // expected-warning {{The right operand to '*' is always 0}} + test(x & zero); // expected-warning {{The right operand to '&' is always 0}} + test(x | zero); // expected-warning {{The right operand to '|' is always 0}} + test(x ^ zero); // expected-warning {{The right operand to '^' is always 0}} + test(x << zero); // expected-warning {{The right operand to '<<' is always 0}} + test(x >> zero); // expected-warning {{The right operand to '>>' is always 0}} // 0 op x - test(zero + x); // expected-warning {{idempotent operation; the left operand is always 0}} - test(zero - x); // expected-warning {{idempotent operation; the left operand is always 0}} - test(zero / x); // expected-warning {{idempotent operation; the left operand is always 0}} - test(zero * x); // expected-warning {{idempotent operation; the left operand is always 0}} - test(zero & x); // expected-warning {{idempotent operation; the left operand is always 0}} - test(zero | x); // expected-warning {{idempotent operation; the left operand is always 0}} - test(zero ^ x); // expected-warning {{idempotent operation; the left operand is always 0}} - test(zero << x); // expected-warning {{idempotent operation; the left operand is always 0}} - test(zero >> x); // expected-warning {{idempotent operation; the left operand is always 0}} + test(zero + x); // expected-warning {{The left operand to '+' is always 0}} + test(zero - x); // expected-warning {{The left operand to '-' is always 0}} + test(zero / x); // expected-warning {{The left operand to '/' is always 0}} + test(zero * x); // expected-warning {{The left operand to '*' is always 0}} + test(zero & x); // expected-warning {{The left operand to '&' is always 0}} + test(zero | x); // expected-warning {{The left operand to '|' is always 0}} + test(zero ^ x); // expected-warning {{The left operand to '^' is always 0}} + test(zero << x); // expected-warning {{The left operand to '<<' is always 0}} + test(zero >> x); // expected-warning {{The left operand to '>>' is always 0}} + + // Overwrite the values so these aren't marked as Pseudoconstants + x = 1; + zero = 2; + one = 3; + + return x + zero + one; +} + +void floats(float x) { + test_f(x * 1.0); // no-warning + test_f(x * 1.0F); // no-warning +} + +// Ensure that we don't report false poitives in complex loops +void bailout() { + int unused = 0, result = 4; + result = result; // expected-warning {{Assigned value is always the same as the existing value}} + + for (unsigned bg = 0; bg < 1024; bg ++) { + result = bg * result; // no-warning + + for (int i = 0; i < 256; i++) { + unused *= i; // no-warning + } + } +} + +// Relaxed liveness - check that we don't kill liveness at assignments +typedef unsigned uintptr_t; +void kill_at_assign() { + short array[2]; + uintptr_t x = array; // expected-warning{{incompatible pointer to integer conversion}} + short *p = x; // expected-warning{{incompatible integer to pointer conversion}} + + // The following branch should be infeasible. + if (!(p = &array[0])) { // expected-warning{{Assigned value is always the same as the existing value}} + p = 0; + *p = 1; // no-warning + } +} + +// False positive tests + +unsigned false1() { + int a = 10; + return a * (5 - 2 - 3); // no-warning +} + +enum testenum { enum1 = 0, enum2 }; +unsigned false2() { + int a = 1234; + return enum1 + a; // no-warning +} + +// Self assignments of unused variables are common false positives +unsigned false3(int param, int param2) { + param = param; // no-warning + + // if a self assigned variable is used later, then it should be reported still + param2 = param2; // expected-warning{{Assigned value is always the same as the existing value}} + + unsigned nonparam = 5; + + nonparam = nonparam; // expected-warning{{Assigned value is always the same as the existing value}} + + return param2 + nonparam; +} + +// Pseudo-constants (vars only read) and constants should not be reported +unsigned false4() { + // Trivial constant + const int height = 1; + int c = 42; + test(height * c); // no-warning + + // Pseudo-constant (never changes after decl) + int width = height; + + return width * 10; // no-warning +} + +// Block pseudoconstants +void false4a() { + // Pseudo-constant + __block int a = 1; + int b = 10; + __block int c = 0; + b *= a; // no-warning + + ^{ + // Psuedoconstant block var + test(b * c); // no-warning + + // Non-pseudoconstant block var + int d = 0; + test(b * d); // expected-warning{{The right operand to '*' is always 0}} + d = 5; + test(d); + }(); + + test(a + b); +} + +// Static vars are common false positives +int false5() { + static int test = 0; + int a = 56; + a *= test; // no-warning + test++; + return a; +} + +// Non-local storage vars are considered false positives +int globalInt = 1; +int false6() { + int localInt = 23; + + localInt /= globalInt; + + return localInt; +} + +// Check that assignments filter out false positives correctly +int false7() { + int zero = 0; // psuedo-constant + int one = 1; + + int a = 55; + a = a; // expected-warning{{Assigned value is always the same as the existing value}} + a = enum1 * a; // no-warning + + int b = 123; + b = b; // no-warning + + return a; } |
