Tom de Vries
3f2e15c2e6
Consider test-case test.c, with VLA A:
...
int main (void) {
int N = 1000;
int A[N];
#pragma acc declare copy(A)
return 0;
}
...
compiled using:
...
$ gcc test.c -fopenacc -S -fdump-tree-all
...
At original, we have:
...
#pragma acc declare map(tofrom:A);
...
but at gimple, we have a map (to:A.1), but not a map (from:A.1):
...
int[0:D.2074] * A.1;
{
int A[0:D.2074] [value-expr: *A.1];
saved_stack.2 = __builtin_stack_save ();
try
{
A.1 = __builtin_alloca_with_align (D.2078, 32);
#pragma omp target oacc_declare map(to:(*A.1) [len: D.2076])
}
finally
{
__builtin_stack_restore (saved_stack.2);
}
}
...
This is caused by the following incompatibility. When storing the desired
from clause in oacc_declare_returns, we use 'A.1' as the key:
...
10898 oacc_declare_returns->put (decl, c);
(gdb) call debug_generic_expr (decl)
A.1
(gdb) call debug_generic_expr (c)
map(from:(*A.1))
...
but when looking it up, we use 'A' as the key:
...
(gdb)
1471 tree *c = oacc_declare_returns->get (t);
(gdb) call debug_generic_expr (t)
A
...
Fix this by extracing the 'A.1' lookup key from 'A' using the decl-expr.
In addition, unshare the looked up value, to fix avoid running into
an "incorrect sharing of tree nodes" error.
Using these two fixes, we get our desired:
...
finally
{
+ #pragma omp target oacc_declare map(from:(*A.1))
__builtin_stack_restore (saved_stack.2);
}
...
Build on x86_64-linux with nvptx accelerator, tested libgomp.
gcc/ChangeLog:
2020-10-06 Tom de Vries <tdevries@suse.de>
PR middle-end/90861
* gimplify.c (gimplify_bind_expr): Handle lookup in
oacc_declare_returns using key with decl-expr.
libgomp/ChangeLog:
2020-10-06 Tom de Vries <tdevries@suse.de>
PR middle-end/90861
* testsuite/libgomp.oacc-c-c++-common/declare-vla.c: Remove xfail.
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