1 #include <petsc/private/petscimpl.h> 2 3 static PetscInt petsc_checkpointer_intensity = 1; 4 5 /*@ 6 PetscCheckPointerSetIntensity - An intense pointer check registers a signal handler and attempts to dereference to 7 confirm whether the address is valid. An intensity of 0 never uses signal handlers, 1 uses them when not in a "hot" 8 function, and intensity of 2 always uses a signal handler. 9 10 Not Collective 11 12 Input Parameter: 13 . intensity - how much to check pointers for validity 14 15 Options Database Key: 16 . -check_pointer_intensity - intensity (0, 1, or 2) 17 18 Level: advanced 19 20 .seealso: `PetscCheckPointer()`, `PetscFunctionBeginHot()` 21 @*/ 22 PetscErrorCode PetscCheckPointerSetIntensity(PetscInt intensity) 23 { 24 PetscFunctionBegin; 25 PetscCheck((intensity >= 0) && (intensity <= 2), PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Intensity %" PetscInt_FMT " not in [0,2]", intensity); 26 petsc_checkpointer_intensity = intensity; 27 PetscFunctionReturn(PETSC_SUCCESS); 28 } 29 30 /* ---------------------------------------------------------------------------------------*/ 31 32 #if PetscDefined(HAVE_SETJMP_H) 33 #include <setjmp.h> 34 static jmp_buf PetscSegvJumpBuf; 35 static PetscBool PetscSegvJumpBuf_set; 36 37 /*@C 38 PetscSignalSegvCheckPointerOrMpi - To be called from a signal handler for SIGSEGV. 39 40 Not Collective 41 42 Notes: 43 If the signal was received while executing PetscCheckPointer(), this function longjmps back 44 there, otherwise returns with no effect. This function is called automatically by 45 PetscSignalHandlerDefault(). 46 47 Level: developer 48 49 .seealso: `PetscPushSignalHandler()` 50 @*/ 51 void PetscSignalSegvCheckPointerOrMpi(void) 52 { 53 if (PetscSegvJumpBuf_set) longjmp(PetscSegvJumpBuf, 1); 54 } 55 56 /*@C 57 PetscCheckPointer - Returns `PETSC_TRUE` if a pointer points to accessible data 58 59 Not Collective 60 61 Input Parameters: 62 + ptr - the pointer 63 - dtype - the type of data the pointer is suppose to point to 64 65 Level: developer 66 67 Note: 68 This is a non-standard PETSc function in that it returns the result as the return code and does not return an error code 69 70 .seealso: `PetscCheckPointerSetIntensity()` 71 @*/ 72 PetscBool PetscCheckPointer(const void *ptr, PetscDataType dtype) 73 { 74 if (PETSC_RUNNING_ON_VALGRIND) return PETSC_TRUE; 75 if (!ptr) return PETSC_FALSE; 76 if (petsc_checkpointer_intensity < 1) return PETSC_TRUE; 77 78 #if PetscDefined(USE_DEBUG) && !PetscDefined(HAVE_THREADSAFETY) 79 /* Skip the verbose check if we are inside a hot function. */ 80 if (petscstack.hotdepth > 0 && petsc_checkpointer_intensity < 2) return PETSC_TRUE; 81 #endif 82 83 PetscSegvJumpBuf_set = PETSC_TRUE; 84 85 if (setjmp(PetscSegvJumpBuf)) { 86 /* A segv was triggered in the code below hence we return with an error code */ 87 PetscSegvJumpBuf_set = PETSC_FALSE; 88 return PETSC_FALSE; 89 } else { 90 switch (dtype) { 91 case PETSC_INT: { 92 PETSC_UNUSED PetscInt x = (PetscInt) * (volatile PetscInt *)ptr; 93 break; 94 } 95 #if defined(PETSC_USE_COMPLEX) 96 case PETSC_SCALAR: { /* C++ is seriously dysfunctional with volatile std::complex. */ 97 #if defined(PETSC_USE_CXXCOMPLEX) 98 PetscReal xreal = ((volatile PetscReal *)ptr)[0], ximag = ((volatile PetscReal *)ptr)[1]; 99 PETSC_UNUSED volatile PetscScalar x = xreal + PETSC_i * ximag; 100 #else 101 PETSC_UNUSED PetscScalar x = *(volatile PetscScalar *)ptr; 102 #endif 103 break; 104 } 105 #endif 106 case PETSC_REAL: { 107 PETSC_UNUSED PetscReal x = *(volatile PetscReal *)ptr; 108 break; 109 } 110 case PETSC_BOOL: { 111 PETSC_UNUSED PetscBool x = *(volatile PetscBool *)ptr; 112 break; 113 } 114 case PETSC_ENUM: { 115 PETSC_UNUSED PetscEnum x = *(volatile PetscEnum *)ptr; 116 break; 117 } 118 case PETSC_CHAR: { 119 PETSC_UNUSED char x = *(volatile char *)ptr; 120 break; 121 } 122 case PETSC_OBJECT: { 123 PETSC_UNUSED volatile PetscClassId classid = ((PetscObject)ptr)->classid; 124 break; 125 } 126 default:; 127 } 128 } 129 PetscSegvJumpBuf_set = PETSC_FALSE; 130 return PETSC_TRUE; 131 } 132 #endif 133