Currently simplify_loads() is broken with exactly the
same error as in simplify_one_symbol().
The core of the problem is that phi-nodes are stored at
the place where the value is needed, where the initial load
was, while phi-nodes must be placed where branches meet.
Temporary fix this removing this 'simplification'.
Note: It's possible to do this a bit less crudely
Note: This patch is kinda useless without the SSA construction
first fixed..
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
---
memops.c | 63 ---------------------------------------------------------------
1 file changed, 63 deletions(-)
diff --git a/memops.c b/memops.c
index aeacdf566..99430e455 100644
--- a/memops.c
+++ b/memops.c
@@ -16,51 +16,6 @@
#include "linearize.h"
#include "flow.h"
-static int find_dominating_parents(pseudo_t pseudo, struct instruction *insn,
- struct basic_block *bb, unsigned long generation, struct pseudo_list **dominators,
- int local)
-{
- struct basic_block *parent;
-
- FOR_EACH_PTR(bb->parents, parent) {
- struct instruction *one;
- struct instruction *br;
- pseudo_t phi;
-
- FOR_EACH_PTR_REVERSE(parent->insns, one) {
- int dominance;
- if (!one->bb)
- continue;
- if (one == insn)
- goto no_dominance;
- dominance = dominates(pseudo, insn, one, local);
- if (dominance < 0) {
- if (one->opcode == OP_LOAD)
- continue;
- return 0;
- }
- if (!dominance)
- continue;
- goto found_dominator;
- } END_FOR_EACH_PTR_REVERSE(one);
-no_dominance:
- if (parent->generation == generation)
- continue;
- parent->generation = generation;
-
- if (!find_dominating_parents(pseudo, insn, parent, generation, dominators, local))
- return 0;
- continue;
-
-found_dominator:
- br = delete_last_instruction(&parent->insns);
- phi = alloc_phi(parent, one->target, one->size);
- phi->ident = phi->ident ? : one->target->ident;
- add_instruction(&parent->insns, br);
- use_pseudo(insn, phi, add_pseudo(dominators, phi));
- } END_FOR_EACH_PTR(parent);
- return 1;
-}
static int address_taken(pseudo_t pseudo)
{
@@ -91,8 +46,6 @@ static void simplify_loads(struct basic_block *bb)
struct instruction *dom;
pseudo_t pseudo = insn->src;
int local = local_pseudo(pseudo);
- struct pseudo_list *dominators;
- unsigned long generation;
/* Check for illegal offsets.. */
check_access(insn);
@@ -117,22 +70,6 @@ static void simplify_loads(struct basic_block *bb)
goto next_load;
}
} END_FOR_EACH_PTR_REVERSE(dom);
-
- /* OK, go find the parents */
- generation = ++bb_generation;
- bb->generation = generation;
- dominators = NULL;
- if (find_dominating_parents(pseudo, insn, bb, generation, &dominators, local)) {
- /* This happens with initial assignments to structures etc.. */
- if (!dominators) {
- if (local) {
- assert(pseudo->type != PSEUDO_ARG);
- convert_load_instruction(insn, value_pseudo(0));
- }
- goto next_load;
- }
- rewrite_load_instruction(insn, dominators);
- }
}
next_load:
/* Do the next one */;
--
2.14.0
--
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