beprefalloc: simplify by using C99
authorMatthias Braun <matthias.braun@kit.edu>
Mon, 6 Aug 2012 09:25:56 +0000 (11:25 +0200)
committerMatthias Braun <matthias.braun@kit.edu>
Thu, 9 Aug 2012 16:35:18 +0000 (18:35 +0200)
ir/be/beprefalloc.c

index 96640cd..09a92bf 100644 (file)
@@ -184,12 +184,11 @@ static block_info_t *get_block_info(ir_node *block)
  */
 static void mark_as_copy_of(ir_node *copy, ir_node *value)
 {
-       ir_node           *original;
        allocation_info_t *info      = get_allocation_info(value);
        allocation_info_t *copy_info = get_allocation_info(copy);
 
        /* find original value */
-       original = info->original_value;
+       ir_node *original = info->original_value;
        if (original != value) {
                info = get_allocation_info(original);
        }
@@ -217,12 +216,10 @@ static void give_penalties_for_limits(const ir_nodeset_t *live_nodes,
                                       float penalty, const unsigned* limited,
                                       ir_node *node)
 {
-       unsigned           r;
-       size_t             n_allowed;
        allocation_info_t *info = get_allocation_info(node);
 
        /* give penalty for all forbidden regs */
-       for (r = 0; r < n_regs; ++r) {
+       for (unsigned r = 0; r < n_regs; ++r) {
                if (rbitset_is_set(limited, r))
                        continue;
 
@@ -234,7 +231,7 @@ static void give_penalties_for_limits(const ir_nodeset_t *live_nodes,
                return;
 
        penalty   *= NEIGHBOR_FACTOR;
-       n_allowed  = rbitset_popcount(limited, n_regs);
+       size_t n_allowed = rbitset_popcount(limited, n_regs);
        if (n_allowed > 1) {
                /* only create a very weak penalty if multiple regs are allowed */
                penalty = (penalty * 0.8f) / n_allowed;
@@ -248,7 +245,7 @@ static void give_penalties_for_limits(const ir_nodeset_t *live_nodes,
                        continue;
 
                neighbor_info = get_allocation_info(neighbor);
-               for (r = 0; r < n_regs; ++r) {
+               for (unsigned r = 0; r < n_regs; ++r) {
                        if (!rbitset_is_set(limited, r))
                                continue;
 
@@ -280,18 +277,13 @@ static void check_defs(const ir_nodeset_t *live_nodes, float weight,
                ir_node           *insn  = skip_Proj(node);
                allocation_info_t *info  = get_allocation_info(node);
                int                arity = get_irn_arity(insn);
-               int                i;
 
                float factor = 1.0f / rbitset_popcount(&req->other_same, arity);
-               for (i = 0; i < arity; ++i) {
-                       ir_node           *op;
-                       unsigned           r;
-                       allocation_info_t *op_info;
-
+               for (int i = 0; i < arity; ++i) {
                        if (!rbitset_is_set(&req->other_same, i))
                                continue;
 
-                       op = get_irn_n(insn, i);
+                       ir_node *op = get_irn_n(insn, i);
 
                        /* if we the value at the should_be_same input doesn't die at the
                         * node, then it is no use to propagate the constraints (since a
@@ -299,8 +291,8 @@ static void check_defs(const ir_nodeset_t *live_nodes, float weight,
                        if (ir_nodeset_contains(live_nodes, op))
                                continue;
 
-                       op_info = get_allocation_info(op);
-                       for (r = 0; r < n_regs; ++r) {
+                       allocation_info_t *op_info = get_allocation_info(op);
+                       for (unsigned r = 0; r < n_regs; ++r) {
                                op_info->prefs[r] += info->prefs[r] * factor;
                        }
                }
@@ -321,10 +313,6 @@ static void analyze_block(ir_node *block, void *data)
        be_liveness_end_of_block(lv, cls, block, &live_nodes);
 
        sched_foreach_reverse(block, node) {
-               allocation_info_t *info;
-               int                i;
-               int                arity;
-
                if (is_Phi(node))
                        break;
 
@@ -336,18 +324,18 @@ static void analyze_block(ir_node *block, void *data)
                }
 
                /* mark last uses */
-               arity = get_irn_arity(node);
+               int arity = get_irn_arity(node);
 
                /* the allocation info node currently only uses 1 unsigned value
                   to mark last used inputs. So we will fail for a node with more than
                   32 inputs. */
+               allocation_info_t *info = get_allocation_info(node);
                if (arity >= (int) sizeof(info->last_uses) * 8) {
                        panic("Node with more than %d inputs not supported yet",
                                        (int) sizeof(info->last_uses) * 8);
                }
 
-               info = get_allocation_info(node);
-               for (i = 0; i < arity; ++i) {
+               for (int i = 0; i < arity; ++i) {
                        ir_node                   *op  = get_irn_n(node, i);
                        const arch_register_req_t *req = arch_get_irn_register_req(op);
                        if (req->cls != cls)
@@ -363,19 +351,17 @@ static void analyze_block(ir_node *block, void *data)
 
                if (create_preferences) {
                        /* update weights based on usage constraints */
-                       for (i = 0; i < arity; ++i) {
-                               const arch_register_req_t *req;
-                               const unsigned            *limited;
-                               ir_node                   *op = get_irn_n(node, i);
-
+                       for (int i = 0; i < arity; ++i) {
+                               ir_node *op = get_irn_n(node, i);
                                if (!arch_irn_consider_in_reg_alloc(cls, op))
                                        continue;
 
-                               req = arch_get_irn_register_req_in(node, i);
+                               const arch_register_req_t *req
+                                       = arch_get_irn_register_req_in(node, i);
                                if (!(req->type & arch_register_req_type_limited))
                                        continue;
 
-                               limited = req->limited;
+                               const unsigned *limited = req->limited;
                                give_penalties_for_limits(&live_nodes, weight * USE_FACTOR,
                                                          limited, op);
                        }
@@ -391,25 +377,21 @@ static void congruence_def(ir_nodeset_t *live_nodes, const ir_node *node)
 
        /* should be same constraint? */
        if (req->type & arch_register_req_type_should_be_same) {
-               const ir_node *insn  = skip_Proj_const(node);
-               int      arity = get_irn_arity(insn);
-               int      i;
-               unsigned node_idx = get_irn_idx(node);
-               node_idx          = uf_find(congruence_classes, node_idx);
-
-               for (i = 0; i < arity; ++i) {
-                       ir_node *op;
-                       int      op_idx;
-                       bool     interferes = false;
+               const ir_node *insn     = skip_Proj_const(node);
+               int            arity    = get_irn_arity(insn);
+               unsigned       node_idx = get_irn_idx(node);
+               node_idx = uf_find(congruence_classes, node_idx);
 
+               for (int i = 0; i < arity; ++i) {
                        if (!rbitset_is_set(&req->other_same, i))
                                continue;
 
-                       op     = get_irn_n(insn, i);
-                       op_idx = get_irn_idx(op);
+                       ir_node *op     = get_irn_n(insn, i);
+                       int      op_idx = get_irn_idx(op);
                        op_idx = uf_find(congruence_classes, op_idx);
 
                        /* do we interfere with the value */
+                       bool interferes = false;
                        foreach_ir_nodeset(live_nodes, live, iter) {
                                int lv_idx = get_irn_idx(live);
                                lv_idx     = uf_find(congruence_classes, lv_idx);
@@ -458,29 +440,22 @@ static void create_congruence_class(ir_node *block, void *data)
 
        /* check phi congruence classes */
        sched_foreach_reverse_from(last_phi, phi) {
-               int i;
-               int arity;
-               int node_idx;
                assert(is_Phi(phi));
 
                if (!arch_irn_consider_in_reg_alloc(cls, phi))
                        continue;
 
-               node_idx = get_irn_idx(phi);
+               int node_idx = get_irn_idx(phi);
                node_idx = uf_find(congruence_classes, node_idx);
 
-               arity = get_irn_arity(phi);
-               for (i = 0; i < arity; ++i) {
-                       bool               interferes = false;
-                       unsigned           r;
-                       int                old_node_idx;
-                       allocation_info_t *head_info;
-                       allocation_info_t *other_info;
-                       ir_node           *op     = get_Phi_pred(phi, i);
-                       int                op_idx = get_irn_idx(op);
+               int arity = get_irn_arity(phi);
+               for (int i = 0; i < arity; ++i) {
+                       ir_node *op     = get_Phi_pred(phi, i);
+                       int      op_idx = get_irn_idx(op);
                        op_idx = uf_find(congruence_classes, op_idx);
 
                        /* do we interfere with the value */
+                       bool interferes = false;
                        foreach_ir_nodeset(&live_nodes, live, iter) {
                                int lv_idx = get_irn_idx(live);
                                lv_idx     = uf_find(congruence_classes, lv_idx);
@@ -514,15 +489,17 @@ static void create_congruence_class(ir_node *block, void *data)
                                continue;
 
                        /* merge the 2 congruence classes and sum up their preferences */
-                       old_node_idx = node_idx;
+                       int old_node_idx = node_idx;
                        node_idx = uf_union(congruence_classes, node_idx, op_idx);
                        DB((dbg, LEVEL_3, "Merge %+F and %+F congruence classes\n",
                            phi, op));
 
                        old_node_idx = node_idx == old_node_idx ? op_idx : old_node_idx;
-                       head_info  = get_allocation_info(get_idx_irn(irg, node_idx));
-                       other_info = get_allocation_info(get_idx_irn(irg, old_node_idx));
-                       for (r = 0; r < n_regs; ++r) {
+                       allocation_info_t *head_info
+                               = get_allocation_info(get_idx_irn(irg, node_idx));
+                       allocation_info_t *other_info
+                               = get_allocation_info(get_idx_irn(irg, old_node_idx));
+                       for (unsigned r = 0; r < n_regs; ++r) {
                                head_info->prefs[r] += other_info->prefs[r];
                        }
                }
@@ -531,13 +508,10 @@ static void create_congruence_class(ir_node *block, void *data)
 
 static void set_congruence_prefs(ir_node *node, void *data)
 {
-       allocation_info_t *info;
-       allocation_info_t *head_info;
+       (void) data;
        unsigned node_idx = get_irn_idx(node);
        unsigned node_set = uf_find(congruence_classes, node_idx);
 
-       (void) data;
-
        /* head of congruence class or not in any class */
        if (node_set == node_idx)
                return;
@@ -545,8 +519,9 @@ static void set_congruence_prefs(ir_node *node, void *data)
        if (!arch_irn_consider_in_reg_alloc(cls, node))
                return;
 
-       head_info = get_allocation_info(get_idx_irn(irg, node_set));
-       info      = get_allocation_info(node);
+       ir_node *head = get_idx_irn(irg, node_set);
+       allocation_info_t *head_info = get_allocation_info(head);
+       allocation_info_t *info      = get_allocation_info(node);
 
        memcpy(info->prefs, head_info->prefs, n_regs * sizeof(info->prefs[0]));
 }
@@ -581,14 +556,11 @@ static void use_reg(ir_node *node, const arch_register_t *reg)
 
 static void free_reg_of_value(ir_node *node)
 {
-       const arch_register_t *reg;
-       unsigned               r;
-
        if (!arch_irn_consider_in_reg_alloc(cls, node))
                return;
 
-       reg        = arch_get_irn_register(node);
-       r          = arch_register_get_index(reg);
+       const arch_register_t *reg = arch_get_irn_register(node);
+       unsigned               r   = arch_register_get_index(reg);
        /* assignment->value may be NULL if a value is used at 2 inputs
           so it gets freed twice. */
        assert(assignments[r] == node || assignments[r] == NULL);
@@ -612,9 +584,7 @@ static int compare_reg_pref(const void *e1, const void *e2)
 static void fill_sort_candidates(reg_pref_t *regprefs,
                                  const allocation_info_t *info)
 {
-       unsigned r;
-
-       for (r = 0; r < n_regs; ++r) {
+       for (unsigned r = 0; r < n_regs; ++r) {
                float pref = info->prefs[r];
                regprefs[r].num  = r;
                regprefs[r].pref = pref;
@@ -627,45 +597,31 @@ static bool try_optimistic_split(ir_node *to_split, ir_node *before,
                                  float pref, float pref_delta,
                                  unsigned *forbidden_regs, int recursion)
 {
-       const arch_register_t *from_reg;
-       const arch_register_t *reg;
-       ir_node               *original_insn;
-       ir_node               *block;
-       ir_node               *copy;
-       unsigned               r = 0;
-       unsigned               from_r;
-       unsigned               i;
-       allocation_info_t     *info = get_allocation_info(to_split);
-       reg_pref_t            *prefs;
-       float                  delta = 0;
-       float                  split_threshold;
-
        (void) pref;
+       unsigned           r = 0;
+       allocation_info_t *info = get_allocation_info(to_split);
+       float              delta = 0;
 
        /* stupid hack: don't optimisticallt split don't spill nodes...
         * (so we don't split away the values produced because of
         *  must_be_different constraints) */
-       original_insn = skip_Proj(info->original_value);
+       ir_node *original_insn = skip_Proj(info->original_value);
        if (arch_get_irn_flags(original_insn) & arch_irn_flags_dont_spill)
                return false;
 
-       from_reg        = arch_get_irn_register(to_split);
-       from_r          = arch_register_get_index(from_reg);
-       block           = get_nodes_block(before);
-       split_threshold = (float)get_block_execfreq(block) * SPLIT_DELTA;
+       const arch_register_t *from_reg        = arch_get_irn_register(to_split);
+       unsigned               from_r          = arch_register_get_index(from_reg);
+       ir_node               *block           = get_nodes_block(before);
+       float split_threshold = (float)get_block_execfreq(block) * SPLIT_DELTA;
 
        if (pref_delta < split_threshold*0.5)
                return false;
 
        /* find the best free position where we could move to */
-       prefs = ALLOCAN(reg_pref_t, n_regs);
+       reg_pref_t *prefs = ALLOCAN(reg_pref_t, n_regs);
        fill_sort_candidates(prefs, info);
+       unsigned i;
        for (i = 0; i < n_regs; ++i) {
-               float apref;
-               float apref_delta;
-               bool  res;
-               bool  old_source_state;
-
                /* we need a normal register which is not an output register
                   an different from the current register of to_split */
                r = prefs[i].num;
@@ -692,17 +648,17 @@ static bool try_optimistic_split(ir_node *to_split, ir_node *before,
                if (recursion+1 > MAX_OPTIMISTIC_SPLIT_RECURSION)
                        continue;
 
-               apref        = prefs[i].pref;
-               apref_delta  = i+1 < n_regs ? apref - prefs[i+1].pref : 0;
+               float apref        = prefs[i].pref;
+               float apref_delta  = i+1 < n_regs ? apref - prefs[i+1].pref : 0;
                apref_delta += pref_delta - split_threshold;
 
                /* our source register isn't a useful destination for recursive
                   splits */
-               old_source_state = rbitset_is_set(forbidden_regs, from_r);
+               bool old_source_state = rbitset_is_set(forbidden_regs, from_r);
                rbitset_set(forbidden_regs, from_r);
                /* try recursive split */
-               res = try_optimistic_split(assignments[r], before, apref,
-                                          apref_delta, forbidden_regs, recursion+1);
+               bool res = try_optimistic_split(assignments[r], before, apref,
+                                             apref_delta, forbidden_regs, recursion+1);
                /* restore our destination */
                if (old_source_state) {
                        rbitset_set(forbidden_regs, from_r);
@@ -716,8 +672,8 @@ static bool try_optimistic_split(ir_node *to_split, ir_node *before,
        if (i >= n_regs)
                return false;
 
-       reg  = arch_register_for_index(cls, r);
-       copy = be_new_Copy(block, to_split);
+       const arch_register_t *reg  = arch_register_for_index(cls, r);
+       ir_node               *copy = be_new_Copy(block, to_split);
        mark_as_copy_of(copy, to_split);
        /* hacky, but correct here */
        if (assignments[arch_register_get_index(from_reg)] == to_split)
@@ -737,48 +693,34 @@ static bool try_optimistic_split(ir_node *to_split, ir_node *before,
 static void assign_reg(const ir_node *block, ir_node *node,
                        unsigned *forbidden_regs)
 {
-       const arch_register_t     *final_reg;
-       allocation_info_t         *info;
-       const arch_register_req_t *req;
-       reg_pref_t                *reg_prefs;
-       ir_node                   *in_node;
-       unsigned                   r;
-       const unsigned            *allowed_regs;
-       unsigned                   final_reg_index = 0;
-
        assert(!is_Phi(node));
        /* preassigned register? */
-       final_reg = arch_get_irn_register(node);
+       const arch_register_t *final_reg = arch_get_irn_register(node);
        if (final_reg != NULL) {
                DB((dbg, LEVEL_2, "Preassignment %+F -> %s\n", node, final_reg->name));
                use_reg(node, final_reg);
                return;
        }
 
-       req = arch_get_irn_register_req(node);
+       const arch_register_req_t *req = arch_get_irn_register_req(node);
        /* ignore reqs must be preassigned */
        assert (! (req->type & arch_register_req_type_ignore));
 
        /* give should_be_same boni */
-       info    = get_allocation_info(node);
-       in_node = skip_Proj(node);
+       allocation_info_t *info    = get_allocation_info(node);
+       ir_node           *in_node = skip_Proj(node);
        if (req->type & arch_register_req_type_should_be_same) {
                float weight = (float)get_block_execfreq(block);
                int   arity  = get_irn_arity(in_node);
-               int   i;
 
                assert(arity <= (int) sizeof(req->other_same) * 8);
-               for (i = 0; i < arity; ++i) {
-                       ir_node               *in;
-                       const arch_register_t *reg;
-                       unsigned               reg_index;
+               for (int i = 0; i < arity; ++i) {
                        if (!rbitset_is_set(&req->other_same, i))
                                continue;
 
-                       in  = get_irn_n(in_node, i);
-                       reg = arch_get_irn_register(in);
-                       assert(reg != NULL);
-                       reg_index = arch_register_get_index(reg);
+                       ir_node               *in        = get_irn_n(in_node, i);
+                       const arch_register_t *reg       = arch_get_irn_register(in);
+                       unsigned               reg_index = arch_register_get_index(reg);
 
                        /* if the value didn't die here then we should not propagate the
                         * should_be_same info */
@@ -791,29 +733,25 @@ static void assign_reg(const ir_node *block, ir_node *node,
 
        /* create list of register candidates and sort by their preference */
        DB((dbg, LEVEL_2, "Candidates for %+F:", node));
-       reg_prefs = ALLOCAN(reg_pref_t, n_regs);
+       reg_pref_t *reg_prefs = ALLOCAN(reg_pref_t, n_regs);
        fill_sort_candidates(reg_prefs, info);
-       for (r = 0; r < n_regs; ++r) {
+       for (unsigned r = 0; r < n_regs; ++r) {
                unsigned num = reg_prefs[r].num;
-               const arch_register_t *reg;
-
                if (!rbitset_is_set(normal_regs, num))
                        continue;
-               reg = arch_register_for_index(cls, num);
+               const arch_register_t *reg = arch_register_for_index(cls, num);
                DB((dbg, LEVEL_2, " %s(%f)", reg->name, reg_prefs[r].pref));
        }
        DB((dbg, LEVEL_2, "\n"));
 
-       allowed_regs = normal_regs;
+       const unsigned *allowed_regs = normal_regs;
        if (req->type & arch_register_req_type_limited) {
                allowed_regs = req->limited;
        }
 
+       unsigned final_reg_index = 0;
+       unsigned r;
        for (r = 0; r < n_regs; ++r) {
-               float   pref, delta;
-               ir_node *before;
-               bool    res;
-
                final_reg_index = reg_prefs[r].num;
                if (!rbitset_is_set(allowed_regs, final_reg_index))
                        continue;
@@ -824,11 +762,12 @@ static void assign_reg(const ir_node *block, ir_node *node,
 
                if (assignments[final_reg_index] == NULL)
                        break;
-               pref   = reg_prefs[r].pref;
-               delta  = r+1 < n_regs ? pref - reg_prefs[r+1].pref : 0;
-               before = skip_Proj(node);
-               res    = try_optimistic_split(assignments[final_reg_index], before,
-                                             pref, delta, forbidden_regs, 0);
+               float    pref   = reg_prefs[r].pref;
+               float    delta  = r+1 < n_regs ? pref - reg_prefs[r+1].pref : 0;
+               ir_node *before = skip_Proj(node);
+               bool     res
+                       = try_optimistic_split(assignments[final_reg_index], before, pref,
+                                              delta, forbidden_regs, 0);
                if (res)
                        break;
        }
@@ -880,12 +819,10 @@ static void assign_reg(const ir_node *block, ir_node *node,
 static void permute_values(ir_nodeset_t *live_nodes, ir_node *before,
                            unsigned *permutation)
 {
-       unsigned  *n_used = ALLOCANZ(unsigned, n_regs);
-       ir_node   *block;
-       unsigned   r;
+       unsigned *n_used = ALLOCANZ(unsigned, n_regs);
 
        /* determine how often each source register needs to be read */
-       for (r = 0; r < n_regs; ++r) {
+       for (unsigned r = 0; r < n_regs; ++r) {
                unsigned  old_reg = permutation[r];
                ir_node  *value;
 
@@ -900,14 +837,11 @@ static void permute_values(ir_nodeset_t *live_nodes, ir_node *before,
                ++n_used[old_reg];
        }
 
-       block = get_nodes_block(before);
+       ir_node *block = get_nodes_block(before);
 
        /* step1: create copies where immediately possible */
-       for (r = 0; r < n_regs; /* empty */) {
-               ir_node *copy;
-               ir_node *src;
-               const arch_register_t *reg;
-               unsigned               old_r = permutation[r];
+       for (unsigned r = 0; r < n_regs; /* empty */) {
+               unsigned old_r = permutation[r];
 
                /* - no need to do anything for fixed points.
                   - we can't copy if the value in the dest reg is still needed */
@@ -917,10 +851,10 @@ static void permute_values(ir_nodeset_t *live_nodes, ir_node *before,
                }
 
                /* create a copy */
-               src  = assignments[old_r];
-               copy = be_new_Copy(block, src);
+               ir_node *src  = assignments[old_r];
+               ir_node *copy = be_new_Copy(block, src);
                sched_add_before(before, copy);
-               reg = arch_register_for_index(cls, r);
+               const arch_register_t *reg = arch_register_for_index(cls, r);
                DB((dbg, LEVEL_2, "Copy %+F (from %+F, before %+F) -> %s\n",
                    copy, src, before, reg->name));
                mark_as_copy_of(copy, src);
@@ -959,14 +893,8 @@ static void permute_values(ir_nodeset_t *live_nodes, ir_node *before,
         *  copies are preferable even for 2-cycles) */
 
        /* create perms with the rest */
-       for (r = 0; r < n_regs; /* empty */) {
-               const arch_register_t *reg;
-               unsigned  old_r = permutation[r];
-               unsigned  r2;
-               ir_node  *in[2];
-               ir_node  *perm;
-               ir_node  *proj0;
-               ir_node  *proj1;
+       for (unsigned r = 0; r < n_regs; /* empty */) {
+               unsigned old_r = permutation[r];
 
                if (old_r == r) {
                        ++r;
@@ -977,24 +905,23 @@ static void permute_values(ir_nodeset_t *live_nodes, ir_node *before,
                assert(n_used[old_r] == 1);
 
                /* exchange old_r and r2; after that old_r is a fixed point */
-               r2 = permutation[old_r];
+               unsigned r2 = permutation[old_r];
 
-               in[0] = assignments[r2];
-               in[1] = assignments[old_r];
-               perm = be_new_Perm(cls, block, 2, in);
+               ir_node *in[2] = { assignments[r2], assignments[old_r] };
+               ir_node *perm = be_new_Perm(cls, block, 2, in);
                sched_add_before(before, perm);
                DB((dbg, LEVEL_2, "Perm %+F (perm %+F,%+F, before %+F)\n",
                    perm, in[0], in[1], before));
 
-               proj0 = new_r_Proj(perm, get_irn_mode(in[0]), 0);
+               ir_node *proj0 = new_r_Proj(perm, get_irn_mode(in[0]), 0);
                mark_as_copy_of(proj0, in[0]);
-               reg = arch_register_for_index(cls, old_r);
-               use_reg(proj0, reg);
+               const arch_register_t *reg0 = arch_register_for_index(cls, old_r);
+               use_reg(proj0, reg0);
 
-               proj1 = new_r_Proj(perm, get_irn_mode(in[1]), 1);
+               ir_node *proj1 = new_r_Proj(perm, get_irn_mode(in[1]), 1);
                mark_as_copy_of(proj1, in[1]);
-               reg = arch_register_for_index(cls, r2);
-               use_reg(proj1, reg);
+               const arch_register_t *reg1 = arch_register_for_index(cls, r2);
+               use_reg(proj1, reg1);
 
                /* 1 value is now in the correct register */
                permutation[old_r] = old_r;
@@ -1012,7 +939,7 @@ static void permute_values(ir_nodeset_t *live_nodes, ir_node *before,
 
 #ifdef DEBUG_libfirm
        /* now we should only have fixpoints left */
-       for (r = 0; r < n_regs; ++r) {
+       for (unsigned r = 0; r < n_regs; ++r) {
                assert(permutation[r] == r);
        }
 #endif
@@ -1029,16 +956,13 @@ static void free_last_uses(ir_nodeset_t *live_nodes, ir_node *node)
        allocation_info_t *info      = get_allocation_info(node);
        const unsigned    *last_uses = info->last_uses;
        int                arity     = get_irn_arity(node);
-       int                i;
-
-       for (i = 0; i < arity; ++i) {
-               ir_node *op;
 
+       for (int i = 0; i < arity; ++i) {
                /* check if one operand is the last use */
                if (!rbitset_is_set(last_uses, i))
                        continue;
 
-               op = get_irn_n(node, i);
+               ir_node *op = get_irn_n(node, i);
                free_reg_of_value(op);
                ir_nodeset_remove(live_nodes, op);
        }
@@ -1049,10 +973,8 @@ static void free_last_uses(ir_nodeset_t *live_nodes, ir_node *node)
  */
 static void rewire_inputs(ir_node *node)
 {
-       int i;
        int arity = get_irn_arity(node);
-
-       for (i = 0; i < arity; ++i) {
+       for (int i = 0; i < arity; ++i) {
                ir_node           *op = get_irn_n(node, i);
                allocation_info_t *info = try_get_allocation_info(op);
 
@@ -1073,12 +995,9 @@ static void rewire_inputs(ir_node *node)
 static void determine_live_through_regs(unsigned *bitset, ir_node *node)
 {
        const allocation_info_t *info = get_allocation_info(node);
-       unsigned r;
-       int i;
-       int arity;
 
        /* mark all used registers as potentially live-through */
-       for (r = 0; r < n_regs; ++r) {
+       for (unsigned r = 0; r < n_regs; ++r) {
                if (assignments[r] == NULL)
                        continue;
                if (!rbitset_is_set(normal_regs, r))
@@ -1088,16 +1007,13 @@ static void determine_live_through_regs(unsigned *bitset, ir_node *node)
        }
 
        /* remove registers of value dying at the instruction */
-       arity = get_irn_arity(node);
-       for (i = 0; i < arity; ++i) {
-               ir_node               *op;
-               const arch_register_t *reg;
-
+       int arity = get_irn_arity(node);
+       for (int i = 0; i < arity; ++i) {
                if (!rbitset_is_set(info->last_uses, i))
                        continue;
 
-               op  = get_irn_n(node, i);
-               reg = arch_get_irn_register(op);
+               ir_node               *op  = get_irn_n(node, i);
+               const arch_register_t *reg = arch_get_irn_register(op);
                rbitset_clear(bitset, arch_register_get_index(reg));
        }
 }
@@ -1107,34 +1023,26 @@ static void solve_lpp(ir_nodeset_t *live_nodes, ir_node *node,
 {
        unsigned *forbidden_edges = rbitset_malloc(n_regs * n_regs);
        int      *lpp_vars        = XMALLOCNZ(int, n_regs*n_regs);
-       int       arity           = get_irn_arity(node);
-       int       i;
-       unsigned  l;
-       unsigned  r;
 
        lpp_t *lpp = lpp_new("prefalloc", lpp_minimize);
        //lpp_set_time_limit(lpp, 20);
        lpp_set_log(lpp, stdout);
 
        /** mark some edges as forbidden */
-       for (i = 0; i < arity; ++i) {
-               ir_node                   *op = get_irn_n(node, i);
-               const arch_register_t     *reg;
-               const arch_register_req_t *req;
-               const unsigned            *limited;
-               unsigned                   current_reg;
-
+       int arity = get_irn_arity(node);
+       for (int i = 0; i < arity; ++i) {
+               ir_node *op = get_irn_n(node, i);
                if (!arch_irn_consider_in_reg_alloc(cls, op))
                        continue;
 
-               req = arch_get_irn_register_req_in(node, i);
+               const arch_register_req_t *req = arch_get_irn_register_req_in(node, i);
                if (!(req->type & arch_register_req_type_limited))
                        continue;
 
-               limited     = req->limited;
-               reg         = arch_get_irn_register(op);
-               current_reg = arch_register_get_index(reg);
-               for (r = 0; r < n_regs; ++r) {
+               const unsigned        *limited     = req->limited;
+               const arch_register_t *reg         = arch_get_irn_register(op);
+               unsigned               current_reg = arch_register_get_index(reg);
+               for (unsigned r = 0; r < n_regs; ++r) {
                        if (rbitset_is_set(limited, r))
                                continue;
 
@@ -1143,7 +1051,7 @@ static void solve_lpp(ir_nodeset_t *live_nodes, ir_node *node,
        }
 
        /* add all combinations, except for not allowed ones */
-       for (l = 0; l < n_regs; ++l) {
+       for (unsigned l = 0; l < n_regs; ++l) {
                if (!rbitset_is_set(normal_regs, l)) {
                        char name[15];
                        snprintf(name, sizeof(name), "%u_to_%u", l, l);
@@ -1151,7 +1059,7 @@ static void solve_lpp(ir_nodeset_t *live_nodes, ir_node *node,
                        continue;
                }
 
-               for (r = 0; r < n_regs; ++r) {
+               for (unsigned r = 0; r < n_regs; ++r) {
                        if (!rbitset_is_set(normal_regs, r))
                                continue;
                        if (rbitset_is_set(forbidden_edges, l*n_regs + r))
@@ -1171,11 +1079,10 @@ static void solve_lpp(ir_nodeset_t *live_nodes, ir_node *node,
                }
        }
        /* add constraints */
-       for (l = 0; l < n_regs; ++l) {
-               int constraint;
+       for (unsigned l = 0; l < n_regs; ++l) {
                /* only 1 destination per register */
-               constraint = -1;
-               for (r = 0; r < n_regs; ++r) {
+               int constraint = -1;
+               for (unsigned r = 0; r < n_regs; ++r) {
                        int var = lpp_vars[l*n_regs+r];
                        if (var == 0)
                                continue;
@@ -1188,7 +1095,7 @@ static void solve_lpp(ir_nodeset_t *live_nodes, ir_node *node,
                }
                /* each destination used by at most 1 value */
                constraint = -1;
-               for (r = 0; r < n_regs; ++r) {
+               for (unsigned r = 0; r < n_regs; ++r) {
                        int var = lpp_vars[r*n_regs+l];
                        if (var == 0)
                                continue;
@@ -1204,37 +1111,34 @@ static void solve_lpp(ir_nodeset_t *live_nodes, ir_node *node,
        lpp_dump_plain(lpp, fopen("lppdump.txt", "w"));
 
        /* solve lpp */
-       {
-               unsigned *assignment;
-               lpp_solve(lpp, be_options.ilp_server, be_options.ilp_solver);
-               if (!lpp_is_sol_valid(lpp))
-                       panic("ilp solution not valid!");
-
-               assignment = ALLOCAN(unsigned, n_regs);
-               for (l = 0; l < n_regs; ++l) {
-                       unsigned dest_reg = (unsigned)-1;
-                       for (r = 0; r < n_regs; ++r) {
-                               int var = lpp_vars[l*n_regs+r];
-                               if (var == 0)
-                                       continue;
-                               double val = lpp_get_var_sol(lpp, var);
-                               if (val == 1) {
-                                       assert(dest_reg == (unsigned)-1);
-                                       dest_reg = r;
-                               }
+       lpp_solve(lpp, be_options.ilp_server, be_options.ilp_solver);
+       if (!lpp_is_sol_valid(lpp))
+               panic("ilp solution not valid!");
+
+       unsigned *assignment = ALLOCAN(unsigned, n_regs);
+       for (unsigned l = 0; l < n_regs; ++l) {
+               unsigned dest_reg = (unsigned)-1;
+               for (unsigned r = 0; r < n_regs; ++r) {
+                       int var = lpp_vars[l*n_regs+r];
+                       if (var == 0)
+                               continue;
+                       double val = lpp_get_var_sol(lpp, var);
+                       if (val == 1) {
+                               assert(dest_reg == (unsigned)-1);
+                               dest_reg = r;
                        }
-                       assert(dest_reg != (unsigned)-1);
-                       assignment[dest_reg] = l;
                }
+               assert(dest_reg != (unsigned)-1);
+               assignment[dest_reg] = l;
+       }
 
-               fprintf(stderr, "Assignment: ");
-               for (l = 0; l < n_regs; ++l) {
-                       fprintf(stderr, "%u ", assignment[l]);
-               }
-               fprintf(stderr, "\n");
-               fflush(stdout);
-               permute_values(live_nodes, node, assignment);
+       fprintf(stderr, "Assignment: ");
+       for (unsigned l = 0; l < n_regs; ++l) {
+               fprintf(stderr, "%u ", assignment[l]);
        }
+       fprintf(stderr, "\n");
+       fflush(stdout);
+       permute_values(live_nodes, node, assignment);
        lpp_free(lpp);
 }
 
@@ -1254,36 +1158,22 @@ static bool is_aligned(unsigned num, unsigned alignment)
 static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node,
                                 unsigned *forbidden_regs)
 {
-       int arity = get_irn_arity(node);
-       int i, res;
-       hungarian_problem_t *bp;
-       unsigned l, r;
-       unsigned *assignment;
-       ir_node  *value;
-
-       /* construct a list of register occupied by live-through values */
-       unsigned *live_through_regs = NULL;
-
        /* see if any use constraints are not met and whether double-width
         * values are involved */
        bool double_width = false;
        bool good = true;
-       for (i = 0; i < arity; ++i) {
-               ir_node                   *op = get_irn_n(node, i);
-               const arch_register_t     *reg;
-               const arch_register_req_t *req;
-               const unsigned            *limited;
-               unsigned                   reg_index;
-
+       int  arity = get_irn_arity(node);
+       for (int i = 0; i < arity; ++i) {
+               ir_node *op = get_irn_n(node, i);
                if (!arch_irn_consider_in_reg_alloc(cls, op))
                        continue;
 
                /* are there any limitations for the i'th operand? */
-               req = arch_get_irn_register_req_in(node, i);
+               const arch_register_req_t *req = arch_get_irn_register_req_in(node, i);
                if (req->width > 1)
                        double_width = true;
-               reg       = arch_get_irn_register(op);
-               reg_index = arch_register_get_index(reg);
+               const arch_register_t *reg       = arch_get_irn_register(op);
+               unsigned               reg_index = arch_register_get_index(reg);
                if (req->type & arch_register_req_type_aligned) {
                        if (!is_aligned(reg_index, req->width)) {
                                good = false;
@@ -1293,7 +1183,7 @@ static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node,
                if (!(req->type & arch_register_req_type_limited))
                        continue;
 
-               limited   = req->limited;
+               const unsigned *limited = req->limited;
                if (!rbitset_is_set(limited, reg_index)) {
                        /* found an assignment outside the limited set */
                        good = false;
@@ -1302,6 +1192,8 @@ static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node,
        }
 
        /* is any of the live-throughs using a constrained output register? */
+       ir_node  *value;
+       unsigned *live_through_regs = NULL;
        be_foreach_definition(node, cls, value,
                if (req_->width > 1)
                        double_width = true;
@@ -1336,16 +1228,17 @@ static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node,
         *       right, destinations left because this will produce the solution
         *       in the format required for permute_values.
         */
-       bp = hungarian_new(n_regs, n_regs, HUNGARIAN_MATCH_PERFECT);
+       hungarian_problem_t *bp
+               = hungarian_new(n_regs, n_regs, HUNGARIAN_MATCH_PERFECT);
 
        /* add all combinations, then remove not allowed ones */
-       for (l = 0; l < n_regs; ++l) {
+       for (unsigned l = 0; l < n_regs; ++l) {
                if (!rbitset_is_set(normal_regs, l)) {
                        hungarian_add(bp, l, l, 1);
                        continue;
                }
 
-               for (r = 0; r < n_regs; ++r) {
+               for (unsigned r = 0; r < n_regs; ++r) {
                        if (!rbitset_is_set(normal_regs, r))
                                continue;
                        /* livethrough values may not use constrainted output registers */
@@ -1357,24 +1250,19 @@ static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node,
                }
        }
 
-       for (i = 0; i < arity; ++i) {
-               ir_node                   *op = get_irn_n(node, i);
-               const arch_register_t     *reg;
-               const arch_register_req_t *req;
-               const unsigned            *limited;
-               unsigned                   current_reg;
-
+       for (int i = 0; i < arity; ++i) {
+               ir_node *op = get_irn_n(node, i);
                if (!arch_irn_consider_in_reg_alloc(cls, op))
                        continue;
 
-               req = arch_get_irn_register_req_in(node, i);
+               const arch_register_req_t *req = arch_get_irn_register_req_in(node, i);
                if (!(req->type & arch_register_req_type_limited))
                        continue;
 
-               limited     = req->limited;
-               reg         = arch_get_irn_register(op);
-               current_reg = arch_register_get_index(reg);
-               for (r = 0; r < n_regs; ++r) {
+               const unsigned        *limited     = req->limited;
+               const arch_register_t *reg         = arch_get_irn_register(op);
+               unsigned               current_reg = arch_register_get_index(reg);
+               for (unsigned r = 0; r < n_regs; ++r) {
                        if (rbitset_is_set(limited, r))
                                continue;
                        hungarian_remove(bp, r, current_reg);
@@ -1384,8 +1272,8 @@ static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node,
        //hungarian_print_cost_matrix(bp, 1);
        hungarian_prepare_cost_matrix(bp, HUNGARIAN_MODE_MAXIMIZE_UTIL);
 
-       assignment = ALLOCAN(unsigned, n_regs);
-       res = hungarian_solve(bp, assignment, NULL, 0);
+       unsigned *assignment = ALLOCAN(unsigned, n_regs);
+       int res = hungarian_solve(bp, assignment, NULL, 0);
        assert(res == 0);
 
 #if 0
@@ -1404,14 +1292,11 @@ static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node,
 /** test whether a node @p n is a copy of the value of node @p of */
 static bool is_copy_of(ir_node *value, ir_node *test_value)
 {
-       allocation_info_t *test_info;
-       allocation_info_t *info;
-
        if (value == test_value)
                return true;
 
-       info      = get_allocation_info(value);
-       test_info = get_allocation_info(test_value);
+       allocation_info_t *info      = get_allocation_info(value);
+       allocation_info_t *test_info = get_allocation_info(test_value);
        return test_info->original_value == info->original_value;
 }
 
@@ -1422,9 +1307,8 @@ static bool is_copy_of(ir_node *value, ir_node *test_value)
  */
 static int find_value_in_block_info(block_info_t *info, ir_node *value)
 {
-       unsigned   r;
        ir_node  **end_assignments = info->assignments;
-       for (r = 0; r < n_regs; ++r) {
+       for (unsigned r = 0; r < n_regs; ++r) {
                ir_node *a_value = end_assignments[r];
 
                if (a_value == NULL)
@@ -1442,49 +1326,37 @@ static int find_value_in_block_info(block_info_t *info, ir_node *value)
  */
 static void add_phi_permutations(ir_node *block, int p)
 {
-       unsigned   r;
-       unsigned  *permutation;
-       ir_node  **old_assignments;
-       bool       need_permutation;
-       ir_node   *phi;
-       ir_node   *pred = get_Block_cfgpred_block(block, p);
-
+       ir_node      *pred      = get_Block_cfgpred_block(block, p);
        block_info_t *pred_info = get_block_info(pred);
 
        /* predecessor not processed yet? nothing to do */
        if (!pred_info->processed)
                return;
 
-       permutation = ALLOCAN(unsigned, n_regs);
-       for (r = 0; r < n_regs; ++r) {
+       unsigned *permutation = ALLOCAN(unsigned, n_regs);
+       for (unsigned r = 0; r < n_regs; ++r) {
                permutation[r] = r;
        }
 
        /* check phi nodes */
-       need_permutation = false;
-       phi = sched_first(block);
+       bool     need_permutation = false;
+       ir_node *phi              = sched_first(block);
        for ( ; is_Phi(phi); phi = sched_next(phi)) {
-               const arch_register_t *reg;
-               const arch_register_t *op_reg;
-               int                    regn;
-               int                    a;
-               ir_node               *op;
-
                if (!arch_irn_consider_in_reg_alloc(cls, phi))
                        continue;
 
-               op = get_Phi_pred(phi, p);
-               a  = find_value_in_block_info(pred_info, op);
+               ir_node *phi_pred = get_Phi_pred(phi, p);
+               int      a        = find_value_in_block_info(pred_info, phi_pred);
                assert(a >= 0);
 
-               reg  = arch_get_irn_register(phi);
-               regn = arch_register_get_index(reg);
+               const arch_register_t *reg  = arch_get_irn_register(phi);
+               int                    regn = arch_register_get_index(reg);
                /* same register? nothing to do */
                if (regn == a)
                        continue;
 
-               op     = pred_info->assignments[a];
-               op_reg = arch_get_irn_register(op);
+               ir_node               *op     = pred_info->assignments[a];
+               const arch_register_t *op_reg = arch_get_irn_register(op);
                /* virtual or joker registers are ok too */
                if ((op_reg->type & arch_register_type_joker)
                                || (op_reg->type & arch_register_type_virtual))
@@ -1496,7 +1368,7 @@ static void add_phi_permutations(ir_node *block, int p)
 
        if (need_permutation) {
                /* permute values at end of predecessor */
-               old_assignments = assignments;
+               ir_node **old_assignments = assignments;
                assignments     = pred_info->assignments;
                permute_values(NULL, be_get_end_of_block_insertion_point(pred),
                               permutation);
@@ -1506,19 +1378,14 @@ static void add_phi_permutations(ir_node *block, int p)
        /* change phi nodes to use the copied values */
        phi = sched_first(block);
        for ( ; is_Phi(phi); phi = sched_next(phi)) {
-               int      a;
-               ir_node *op;
-
                if (!arch_irn_consider_in_reg_alloc(cls, phi))
                        continue;
 
-               op = get_Phi_pred(phi, p);
-
                /* we have permuted all values into the correct registers so we can
                   simply query which value occupies the phis register in the
                   predecessor */
-               a  = arch_register_get_index(arch_get_irn_register(phi));
-               op = pred_info->assignments[a];
+               int      a  = arch_register_get_index(arch_get_irn_register(phi));
+               ir_node *op = pred_info->assignments[a];
                set_Phi_pred(phi, p, op);
        }
 }
@@ -1529,32 +1396,27 @@ static void add_phi_permutations(ir_node *block, int p)
  */
 static void adapt_phi_prefs(ir_node *phi)
 {
-       int i;
-       int arity = get_irn_arity(phi);
        ir_node           *block = get_nodes_block(phi);
        allocation_info_t *info  = get_allocation_info(phi);
 
-       for (i = 0; i < arity; ++i) {
+       int arity = get_irn_arity(phi);
+       for (int i = 0; i < arity; ++i) {
                ir_node               *op  = get_irn_n(phi, i);
                const arch_register_t *reg = arch_get_irn_register(op);
-               ir_node               *pred_block;
-               block_info_t          *pred_block_info;
-               float                  weight;
-               unsigned               r;
 
                if (reg == NULL)
                        continue;
                /* we only give the bonus if the predecessor already has registers
                 * assigned, otherwise we only see a dummy value
                 * and any conclusions about its register are useless */
-               pred_block = get_Block_cfgpred_block(block, i);
-               pred_block_info = get_block_info(pred_block);
+               ir_node      *pred_block      = get_Block_cfgpred_block(block, i);
+               block_info_t *pred_block_info = get_block_info(pred_block);
                if (!pred_block_info->processed)
                        continue;
 
                /* give bonus for already assigned register */
-               weight = (float)get_block_execfreq(pred_block);
-               r      = arch_register_get_index(reg);
+               float    weight = (float)get_block_execfreq(pred_block);
+               unsigned r      = arch_register_get_index(reg);
                info->prefs[r] += weight * AFF_PHI;
        }
 }
@@ -1565,15 +1427,13 @@ static void adapt_phi_prefs(ir_node *phi)
  */
 static void propagate_phi_register(ir_node *phi, unsigned assigned_r)
 {
-       int      i;
        ir_node *block = get_nodes_block(phi);
-       int      arity = get_irn_arity(phi);
 
-       for (i = 0; i < arity; ++i) {
+       int arity = get_irn_arity(phi);
+       for (int i = 0; i < arity; ++i) {
                ir_node           *op         = get_Phi_pred(phi, i);
                allocation_info_t *info       = get_allocation_info(op);
                ir_node           *pred_block = get_Block_cfgpred_block(block, i);
-               unsigned           r;
                float              weight
                        = (float)get_block_execfreq(pred_block) * AFF_PHI;
 
@@ -1581,7 +1441,7 @@ static void propagate_phi_register(ir_node *phi, unsigned assigned_r)
                        continue;
 
                /* promote the prefered register */
-               for (r = 0; r < n_regs; ++r) {
+               for (unsigned r = 0; r < n_regs; ++r) {
                        if (info->prefs[r] > -weight) {
                                info->prefs[r] = -weight;
                        }
@@ -1595,13 +1455,8 @@ static void propagate_phi_register(ir_node *phi, unsigned assigned_r)
 
 static void assign_phi_registers(ir_node *block)
 {
-       int                  n_phis = 0;
-       int                  n;
-       int                  res;
-       unsigned            *assignment;
-       hungarian_problem_t *bp;
-
        /* count phi nodes */
+       int n_phis = 0;
        sched_foreach(block, node) {
                if (!is_Phi(node))
                        break;
@@ -1614,12 +1469,10 @@ static void assign_phi_registers(ir_node *block)
                return;
 
        /* build a bipartite matching problem for all phi nodes */
-       bp = hungarian_new(n_phis, n_regs, HUNGARIAN_MATCH_PERFECT);
-       n  = 0;
+       hungarian_problem_t *bp
+               = hungarian_new(n_phis, n_regs, HUNGARIAN_MATCH_PERFECT);
+       int n = 0;
        sched_foreach(block, node) {
-               unsigned r;
-
-               allocation_info_t *info;
                if (!is_Phi(node))
                        break;
                if (!arch_irn_consider_in_reg_alloc(cls, node))
@@ -1628,15 +1481,13 @@ static void assign_phi_registers(ir_node *block)
                /* give boni for predecessor colorings */
                adapt_phi_prefs(node);
                /* add stuff to bipartite problem */
-               info = get_allocation_info(node);
+               allocation_info_t *info = get_allocation_info(node);
                DB((dbg, LEVEL_3, "Prefs for %+F: ", node));
-               for (r = 0; r < n_regs; ++r) {
-                       float costs;
-
+               for (unsigned r = 0; r < n_regs; ++r) {
                        if (!rbitset_is_set(normal_regs, r))
                                continue;
 
-                       costs = info->prefs[r];
+                       float costs = info->prefs[r];
                        costs = costs < 0 ? -logf(-costs+1) : logf(costs+1);
                        costs *= 100;
                        costs += 10000;
@@ -1651,24 +1502,21 @@ static void assign_phi_registers(ir_node *block)
        //hungarian_print_cost_matrix(bp, 7);
        hungarian_prepare_cost_matrix(bp, HUNGARIAN_MODE_MAXIMIZE_UTIL);
 
-       assignment = ALLOCAN(unsigned, n_regs);
-       res        = hungarian_solve(bp, assignment, NULL, 0);
+       unsigned *assignment = ALLOCAN(unsigned, n_regs);
+       int       res        = hungarian_solve(bp, assignment, NULL, 0);
        assert(res == 0);
 
        /* apply results */
        n = 0;
        sched_foreach(block, node) {
-               unsigned               r;
-               const arch_register_t *reg;
-
                if (!is_Phi(node))
                        break;
                if (!arch_irn_consider_in_reg_alloc(cls, node))
                        continue;
 
-               r = assignment[n++];
+               unsigned r = assignment[n++];
                assert(rbitset_is_set(normal_regs, r));
-               reg = arch_register_for_index(cls, r);
+               const arch_register_t *reg = arch_register_for_index(cls, r);
                DB((dbg, LEVEL_2, "Assign %+F -> %s\n", node, reg->name));
                use_reg(node, reg);
 
@@ -1684,42 +1532,30 @@ static void assign_phi_registers(ir_node *block)
  */
 static void allocate_coalesce_block(ir_node *block, void *data)
 {
-       ir_nodeset_t   live_nodes;
-       int            n_preds;
-       block_info_t  *block_info;
-       block_info_t **pred_block_infos;
-       ir_node      **phi_ins;
-       unsigned      *forbidden_regs; /**< collects registers which must
-                                               not be used for optimistic splits */
-
        (void) data;
        DB((dbg, LEVEL_2, "* Block %+F\n", block));
 
        /* clear assignments */
-       block_info  = get_block_info(block);
+       block_info_t *block_info  = get_block_info(block);
        assignments = block_info->assignments;
 
+       ir_nodeset_t live_nodes;
        ir_nodeset_init(&live_nodes);
 
        /* gather regalloc infos of predecessor blocks */
-       n_preds          = get_Block_n_cfgpreds(block);
-       pred_block_infos = ALLOCAN(block_info_t*, n_preds);
+       int            n_preds          = get_Block_n_cfgpreds(block);
+       block_info_t **pred_block_infos = ALLOCAN(block_info_t*, n_preds);
        for (int i = 0; i < n_preds; ++i) {
                ir_node      *pred      = get_Block_cfgpred_block(block, i);
                block_info_t *pred_info = get_block_info(pred);
                pred_block_infos[i]     = pred_info;
        }
 
-       phi_ins = ALLOCAN(ir_node*, n_preds);
+       ir_node **phi_ins = ALLOCAN(ir_node*, n_preds);
 
        /* collect live-in nodes and preassigned values */
        be_lv_foreach(lv, block, be_lv_state_in, node) {
-               bool                       need_phi = false;
-               const arch_register_req_t *req;
-               const arch_register_t     *reg;
-               int                        p;
-
-               req  = arch_get_irn_register_req(node);
+               const arch_register_req_t *req = arch_get_irn_register_req(node);
                if (req->cls != cls)
                        continue;
 
@@ -1727,7 +1563,7 @@ static void allocate_coalesce_block(ir_node *block, void *data)
                        allocation_info_t *info = get_allocation_info(node);
                        info->current_value = node;
 
-                       reg = arch_get_irn_register(node);
+                       const arch_register_t *reg = arch_get_irn_register(node);
                        assert(reg != NULL); /* ignore values must be preassigned */
                        use_reg(node, reg);
                        continue;
@@ -1736,7 +1572,8 @@ static void allocate_coalesce_block(ir_node *block, void *data)
                /* check all predecessors for this value, if it is not everywhere the
                   same or unknown then we have to construct a phi
                   (we collect the potential phi inputs here) */
-               for (p = 0; p < n_preds; ++p) {
+               bool need_phi = false;
+               for (int p = 0; p < n_preds; ++p) {
                        block_info_t *pred_info = pred_block_infos[p];
 
                        if (!pred_info->processed) {
@@ -1763,13 +1600,10 @@ static void allocate_coalesce_block(ir_node *block, void *data)
 
                        DB((dbg, LEVEL_3, "Create Phi %+F (for %+F) -", phi, node));
 #ifdef DEBUG_libfirm
-                       {
-                               int pi;
-                               for (pi = 0; pi < n_preds; ++pi) {
-                                       DB((dbg, LEVEL_3, " %+F", phi_ins[pi]));
-                               }
-                               DB((dbg, LEVEL_3, "\n"));
+                       for (int pi = 0; pi < n_preds; ++pi) {
+                               DB((dbg, LEVEL_3, " %+F", phi_ins[pi]));
                        }
+                       DB((dbg, LEVEL_3, "\n"));
 #endif
                        mark_as_copy_of(phi, node);
                        sched_add_after(block, phi);
@@ -1786,7 +1620,7 @@ static void allocate_coalesce_block(ir_node *block, void *data)
                }
 
                /* if the node already has a register assigned use it */
-               reg = arch_get_irn_register(node);
+               const arch_register_t *reg = arch_get_irn_register(node);
                if (reg != NULL) {
                        use_reg(node, reg);
                }
@@ -1795,6 +1629,8 @@ static void allocate_coalesce_block(ir_node *block, void *data)
                ir_nodeset_insert(&live_nodes, node);
        }
 
+       unsigned      *forbidden_regs; /**< collects registers which must
+                                           not be used for optimistic splits */
        rbitset_alloca(forbidden_regs, n_regs);
 
        /* handle phis... */
@@ -1810,9 +1646,6 @@ static void allocate_coalesce_block(ir_node *block, void *data)
 
        /* assign instructions in the block */
        sched_foreach(block, node) {
-               int arity;
-               ir_node *value;
-
                /* phis are already assigned */
                if (is_Phi(node))
                        continue;
@@ -1826,14 +1659,13 @@ static void allocate_coalesce_block(ir_node *block, void *data)
                rewire_inputs(node);
 
                /* we may not use registers used for inputs for optimistic splits */
-               arity = get_irn_arity(node);
+               int arity = get_irn_arity(node);
                for (int i = 0; i < arity; ++i) {
                        ir_node *op = get_irn_n(node, i);
-                       const arch_register_t *reg;
                        if (!arch_irn_consider_in_reg_alloc(cls, op))
                                continue;
 
-                       reg = arch_get_irn_register(op);
+                       const arch_register_t *reg = arch_get_irn_register(op);
                        rbitset_set(forbidden_regs, arch_register_get_index(reg));
                }
 
@@ -1841,6 +1673,7 @@ static void allocate_coalesce_block(ir_node *block, void *data)
                free_last_uses(&live_nodes, node);
 
                /* assign output registers */
+               ir_node *value;
                be_foreach_definition_(node, cls, value,
                        assign_reg(block, value, forbidden_regs);
                );
@@ -1853,8 +1686,7 @@ static void allocate_coalesce_block(ir_node *block, void *data)
 
        /* permute values at end of predecessor blocks in case of phi-nodes */
        if (n_preds > 1) {
-               int p;
-               for (p = 0; p < n_preds; ++p) {
+               for (int p = 0; p < n_preds; ++p) {
                        add_phi_permutations(block, p);
                }
        }
@@ -1891,7 +1723,6 @@ static int cmp_block_costs(const void *d1, const void *d2)
 
 static void determine_block_order(void)
 {
-       size_t    p;
        ir_node **blocklist = be_get_cfgpostorder(irg);
        size_t    n_blocks  = ARR_LEN(blocklist);
        int       dfs_num   = 0;
@@ -1900,7 +1731,7 @@ static void determine_block_order(void)
        size_t    order_p   = 0;
 
        /* clear block links... */
-       for (p = 0; p < n_blocks; ++p) {
+       for (size_t p = 0; p < n_blocks; ++p) {
                ir_node *block = blocklist[p];
                set_irn_link(block, NULL);
        }
@@ -1908,15 +1739,14 @@ static void determine_block_order(void)
        /* walk blocks in reverse postorder, the costs for each block are the
         * sum of the costs of its predecessors (excluding the costs on backedges
         * which we can't determine) */
-       for (p = n_blocks; p > 0;) {
+       for (size_t p = n_blocks; p > 0;) {
                block_costs_t *cost_info;
                ir_node *block = blocklist[--p];
 
                float execfreq   = (float)get_block_execfreq(block);
                float costs      = execfreq;
                int   n_cfgpreds = get_Block_n_cfgpreds(block);
-               int   p2;
-               for (p2 = 0; p2 < n_cfgpreds; ++p2) {
+               for (int p2 = 0; p2 < n_cfgpreds; ++p2) {
                        ir_node       *pred_block = get_Block_cfgpred_block(block, p2);
                        block_costs_t *pred_costs = (block_costs_t*)get_irn_link(pred_block);
                        /* we don't have any info for backedges */
@@ -1937,8 +1767,8 @@ static void determine_block_order(void)
        ir_reserve_resources(irg, IR_RESOURCE_BLOCK_VISITED);
        inc_irg_block_visited(irg);
 
-       for (p = 0; p < n_blocks; ++p) {
-               ir_node       *block = blocklist[p];
+       for (size_t p = 0; p < n_blocks; ++p) {
+               ir_node *block = blocklist[p];
                if (Block_block_visited(block))
                        continue;
 
@@ -1949,11 +1779,10 @@ static void determine_block_order(void)
                        ir_node       *best_pred  = NULL;
                        float          best_costs = -1;
                        int            n_cfgpred  = get_Block_n_cfgpreds(block);
-                       int            i;
 
                        pdeq_putr(worklist, block);
                        mark_Block_block_visited(block);
-                       for (i = 0; i < n_cfgpred; ++i) {
+                       for (int i = 0; i < n_cfgpred; ++i) {
                                ir_node       *pred_block = get_Block_cfgpred_block(block, i);
                                block_costs_t *pred_info  = (block_costs_t*)get_irn_link(pred_block);
 
@@ -1995,8 +1824,6 @@ static void determine_block_order(void)
  */
 static void be_pref_alloc_cls(void)
 {
-       size_t i;
-
        be_assure_live_sets(irg);
        lv = be_get_irg_liveness(irg);
 
@@ -2010,7 +1837,7 @@ static void be_pref_alloc_cls(void)
        if (create_congruence_classes)
                combine_congruence_classes();
 
-       for (i = 0; i < n_block_order; ++i) {
+       for (size_t i = 0; i < n_block_order; ++i) {
                ir_node *block = block_order[i];
                allocate_coalesce_block(block, NULL);
        }
@@ -2053,10 +1880,6 @@ static void spill(void)
  */
 static void be_pref_alloc(ir_graph *new_irg)
 {
-       const arch_env_t *arch_env = be_get_irg_arch_env(new_irg);
-       int   n_cls                = arch_env->n_register_classes;
-       int   c;
-
        obstack_init(&obst);
 
        irg = new_irg;
@@ -2064,7 +1887,9 @@ static void be_pref_alloc(ir_graph *new_irg)
        /* determine a good coloring order */
        determine_block_order();
 
-       for (c = 0; c < n_cls; ++c) {
+       const arch_env_t *arch_env = be_get_irg_arch_env(new_irg);
+       int               n_cls    = arch_env->n_register_classes;
+       for (int c = 0; c < n_cls; ++c) {
                cls = &arch_env->register_classes[c];
                if (arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
                        continue;