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/* -----------------------------------------------------------------------------
*
* (c) The University of Glasgow 2006-2017
*
* Introspection into GHC's heap representation
*
* ---------------------------------------------------------------------------*/
#include "Rts.h"
#include "RtsAPI.h"
#include "Capability.h"
#include "Printer.h"
StgWord heap_view_closureSize(StgClosure *closure) {
ASSERT(LOOKS_LIKE_CLOSURE_PTR(closure));
return closure_sizeW(closure);
}
static void
heap_view_closure_ptrs_in_large_bitmap(StgClosure *ptrs[], StgWord *nptrs
, StgClosure **p, StgLargeBitmap *large_bitmap
, uint32_t size )
{
uint32_t i, j, b;
StgWord bitmap;
b = 0;
for (i = 0; i < size; b++) {
bitmap = large_bitmap->bitmap[b];
j = stg_min(size-i, BITS_IN(W_));
i += j;
for (; j > 0; j--, p++) {
if ((bitmap & 1) == 0) {
ptrs[(*nptrs)++] = *p;
}
bitmap = bitmap >> 1;
}
}
}
void heap_view_closure_ptrs_in_pap_payload(StgClosure *ptrs[], StgWord *nptrs
, StgClosure *fun, StgClosure **payload, StgWord size) {
StgWord bitmap;
const StgFunInfoTable *fun_info;
fun_info = get_fun_itbl(UNTAG_CLOSURE(fun));
// ASSERT(fun_info->i.type != PAP);
StgClosure **p = payload;
switch (fun_info->f.fun_type) {
case ARG_GEN:
bitmap = BITMAP_BITS(fun_info->f.b.bitmap);
goto small_bitmap;
case ARG_GEN_BIG:
heap_view_closure_ptrs_in_large_bitmap(ptrs, nptrs, payload,
GET_FUN_LARGE_BITMAP(fun_info), size);
break;
case ARG_BCO:
heap_view_closure_ptrs_in_large_bitmap(ptrs, nptrs, payload,
BCO_BITMAP(fun), size);
break;
default:
bitmap = BITMAP_BITS(stg_arg_bitmaps[fun_info->f.fun_type]);
small_bitmap:
while (size > 0) {
if ((bitmap & 1) == 0) {
ptrs[(*nptrs)++] = *p;
}
bitmap = bitmap >> 1;
p++;
size--;
}
break;
}
}
// See Heap.h
StgWord collect_pointers(StgClosure *closure, StgWord size, StgClosure *ptrs[size]) {
StgClosure **end;
const StgInfoTable *info = get_itbl(closure);
StgWord nptrs = 0;
StgWord i;
switch (info->type) {
case INVALID_OBJECT:
barf("Invalid Object");
break;
// No pointers
case ARR_WORDS:
case STACK:
break;
// Default layout
case CONSTR_1_0:
case CONSTR_0_1:
case CONSTR_2_0:
case CONSTR_1_1:
case CONSTR_0_2:
case CONSTR:
case CONSTR_NOCAF:
case PRIM:
case FUN:
case FUN_1_0:
case FUN_0_1:
case FUN_1_1:
case FUN_2_0:
case FUN_0_2:
case FUN_STATIC:
end = closure->payload + info->layout.payload.ptrs;
for (StgClosure **ptr = closure->payload; ptr < end; ptr++) {
ptrs[nptrs++] = *ptr;
}
break;
case THUNK:
case THUNK_1_0:
case THUNK_0_1:
case THUNK_1_1:
case THUNK_2_0:
case THUNK_0_2:
case THUNK_STATIC:
end = ((StgThunk *)closure)->payload + info->layout.payload.ptrs;
for (StgClosure **ptr = ((StgThunk *)closure)->payload; ptr < end; ptr++) {
ptrs[nptrs++] = *ptr;
}
break;
case THUNK_SELECTOR:
ptrs[nptrs++] = ((StgSelector *)closure)->selectee;
break;
case AP:
ptrs[nptrs++] = ((StgAP *)closure)->fun;
heap_view_closure_ptrs_in_pap_payload(ptrs, &nptrs,
((StgAP *)closure)->fun,
((StgAP *)closure)->payload,
((StgAP *)closure)->n_args);
break;
case PAP:
ptrs[nptrs++] = ((StgPAP *)closure)->fun;
heap_view_closure_ptrs_in_pap_payload(ptrs, &nptrs,
((StgPAP *)closure)->fun,
((StgPAP *)closure)->payload,
((StgPAP *)closure)->n_args);
break;
case AP_STACK:
ptrs[nptrs++] = ((StgAP_STACK *)closure)->fun;
/*
The payload is a stack, which consists of a mixture of pointers
and non-pointers. We can't simply pretend it's all pointers,
because that will cause crashes in the GC later. We could
traverse the stack and extract pointers and non-pointers, but that
would be complicated, so let's just ignore the payload for now.
See #15375.
*/
break;
case BCO:
ptrs[nptrs++] = (StgClosure *)((StgBCO *)closure)->instrs;
ptrs[nptrs++] = (StgClosure *)((StgBCO *)closure)->literals;
ptrs[nptrs++] = (StgClosure *)((StgBCO *)closure)->ptrs;
break;
case IND:
case IND_STATIC:
case BLACKHOLE:
ptrs[nptrs++] = (StgClosure *)(((StgInd *)closure)->indirectee);
break;
case MUT_ARR_PTRS_CLEAN:
case MUT_ARR_PTRS_DIRTY:
case MUT_ARR_PTRS_FROZEN_CLEAN:
case MUT_ARR_PTRS_FROZEN_DIRTY:
for (i = 0; i < ((StgMutArrPtrs *)closure)->ptrs; ++i) {
ptrs[nptrs++] = ((StgMutArrPtrs *)closure)->payload[i];
}
break;
case SMALL_MUT_ARR_PTRS_CLEAN:
case SMALL_MUT_ARR_PTRS_DIRTY:
case SMALL_MUT_ARR_PTRS_FROZEN_CLEAN:
case SMALL_MUT_ARR_PTRS_FROZEN_DIRTY:
for (i = 0; i < ((StgSmallMutArrPtrs *)closure)->ptrs; ++i) {
ptrs[nptrs++] = ((StgSmallMutArrPtrs *)closure)->payload[i];
}
break;
case MUT_VAR_CLEAN:
case MUT_VAR_DIRTY:
ptrs[nptrs++] = ((StgMutVar *)closure)->var;
break;
case MVAR_DIRTY:
case MVAR_CLEAN:
ptrs[nptrs++] = (StgClosure *)((StgMVar *)closure)->head;
ptrs[nptrs++] = (StgClosure *)((StgMVar *)closure)->tail;
ptrs[nptrs++] = ((StgMVar *)closure)->value;
break;
case TSO:
ASSERT((StgClosure *)((StgTSO *)closure)->_link != NULL);
ptrs[nptrs++] = (StgClosure *)((StgTSO *)closure)->_link;
ASSERT((StgClosure *)((StgTSO *)closure)->global_link != NULL);
ptrs[nptrs++] = (StgClosure *)((StgTSO *)closure)->global_link;
ASSERT((StgClosure *)((StgTSO *)closure)->stackobj != NULL);
ptrs[nptrs++] = (StgClosure *)((StgTSO *)closure)->stackobj;
ASSERT((StgClosure *)((StgTSO *)closure)->trec != NULL);
ptrs[nptrs++] = (StgClosure *)((StgTSO *)closure)->trec;
ASSERT((StgClosure *)((StgTSO *)closure)->blocked_exceptions != NULL);
ptrs[nptrs++] = (StgClosure *)((StgTSO *)closure)->blocked_exceptions;
ASSERT((StgClosure *)((StgTSO *)closure)->bq != NULL);
ptrs[nptrs++] = (StgClosure *)((StgTSO *)closure)->bq;
break;
case WEAK:
ptrs[nptrs++] = (StgClosure *)((StgWeak *)closure)->cfinalizers;
ptrs[nptrs++] = (StgClosure *)((StgWeak *)closure)->key;
ptrs[nptrs++] = (StgClosure *)((StgWeak *)closure)->value;
ptrs[nptrs++] = (StgClosure *)((StgWeak *)closure)->finalizer;
ptrs[nptrs++] = (StgClosure *)((StgWeak *)closure)->link;
break;
default:
fprintf(stderr,"closurePtrs: Cannot handle type %s yet\n",
closure_type_names[info->type]);
break;
}
return nptrs;
}
StgMutArrPtrs *heap_view_closurePtrs(Capability *cap, StgClosure *closure) {
ASSERT(LOOKS_LIKE_CLOSURE_PTR(closure));
StgWord size = heap_view_closureSize(closure);
// First collect all pointers here, with the comfortable memory bound
// of the whole closure. Afterwards we know how many pointers are in
// the closure and then we can allocate space on the heap and copy them
// there
StgClosure *ptrs[size];
StgWord nptrs = collect_pointers(closure, size, ptrs);
size = nptrs + mutArrPtrsCardTableSize(nptrs);
StgMutArrPtrs *arr =
(StgMutArrPtrs *)allocate(cap, sizeofW(StgMutArrPtrs) + size);
TICK_ALLOC_PRIM(sizeofW(StgMutArrPtrs), nptrs, 0);
SET_HDR(arr, &stg_MUT_ARR_PTRS_FROZEN_CLEAN_info, cap->r.rCCCS);
arr->ptrs = nptrs;
arr->size = size;
for (StgWord i = 0; i<nptrs; i++) {
arr->payload[i] = ptrs[i];
}
return arr;
}
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