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authorKazu Hirata <kazu@cs.umass.edu>2004-11-09 17:41:23 +0000
committerKazu Hirata <kazu@gcc.gnu.org>2004-11-09 17:41:23 +0000
commit2223a9984d66e956e23a3b09c5ef8b4219ec1286 (patch)
tree8fee64000e007e346136c014c6f073922d15fa0d /gcc/conflict.c
parent9965c9c737652dbb0f20aba9daec516288aa5999 (diff)
downloadgcc-2223a9984d66e956e23a3b09c5ef8b4219ec1286.tar.gz
conflict.c (mark_reg, [...]): Remove.
* conflict.c (mark_reg, conflict_graph_compute): Remove. * basic-block.h: Remove the prototype for conflict_graph_compute. From-SVN: r90354
Diffstat (limited to 'gcc/conflict.c')
-rw-r--r--gcc/conflict.c136
1 files changed, 0 insertions, 136 deletions
diff --git a/gcc/conflict.c b/gcc/conflict.c
index ebb40566b42..1cd58600b1e 100644
--- a/gcc/conflict.c
+++ b/gcc/conflict.c
@@ -117,7 +117,6 @@ struct conflict_graph_def
static hashval_t arc_hash (const void *);
static int arc_eq (const void *, const void *);
static int print_conflict (int, int, void *);
-static void mark_reg (rtx, rtx, void *);
/* Callback function to compute the hash value of an arc. Uses
current_graph to locate the graph to which the arc belongs. */
@@ -364,138 +363,3 @@ conflict_graph_print (conflict_graph graph, FILE *fp)
fputc ('\n', fp);
}
}
-
-/* Callback function for note_stores. */
-
-static void
-mark_reg (rtx reg, rtx setter ATTRIBUTE_UNUSED, void *data)
-{
- regset set = (regset) data;
-
- if (GET_CODE (reg) == SUBREG)
- reg = SUBREG_REG (reg);
-
- /* We're only interested in regs. */
- if (!REG_P (reg))
- return;
-
- SET_REGNO_REG_SET (set, REGNO (reg));
-}
-
-/* Allocates a conflict graph and computes conflicts over the current
- function for the registers set in REGS. The caller is responsible
- for deallocating the return value.
-
- Preconditions: the flow graph must be in SSA form, and life
- analysis (specifically, regs live at exit from each block) must be
- up-to-date.
-
- This algorithm determines conflicts by walking the insns in each
- block backwards. We maintain the set of live regs at each insn,
- starting with the regs live on exit from the block. For each insn:
-
- 1. If a reg is set in this insns, it must be born here, since
- we're in SSA. Therefore, it was not live before this insns,
- so remove it from the set of live regs.
-
- 2. For each reg born in this insn, record a conflict between it
- and every other reg live coming into this insn. For each
- existing conflict, one of the two regs must be born while the
- other is alive. See Morgan or elsewhere for a proof of this.
-
- 3. Regs clobbered by this insn must have been live coming into
- it, so record them as such.
-
- The resulting conflict graph is not built for regs in REGS
- themselves; rather, partition P is used to obtain the canonical reg
- for each of these. The nodes of the conflict graph are these
- canonical regs instead. */
-
-conflict_graph
-conflict_graph_compute (regset regs, partition p)
-{
- conflict_graph graph = conflict_graph_new (max_reg_num ());
- regset_head live_head;
- regset live = &live_head;
- regset_head born_head;
- regset born = &born_head;
- basic_block bb;
-
- INIT_REG_SET (live);
- INIT_REG_SET (born);
-
- FOR_EACH_BB_REVERSE (bb)
- {
- rtx insn;
- rtx head;
-
- /* Start with the regs that are live on exit, limited to those
- we're interested in. */
- COPY_REG_SET (live, bb->global_live_at_end);
- AND_REG_SET (live, regs);
-
- /* Walk the instruction stream backwards. */
- head = BB_HEAD (bb);
- insn = BB_END (bb);
- for (insn = BB_END (bb); insn != head; insn = PREV_INSN (insn))
- {
- unsigned born_reg;
- unsigned live_reg;
- rtx link;
-
- /* Are we interested in this insn? */
- if (INSN_P (insn))
- {
- reg_set_iterator rsi;
-
- /* Determine which regs are set in this insn. Since
- we're in SSA form, if a reg is set here it isn't set
- anywhere else, so this insn is where the reg is born. */
- CLEAR_REG_SET (born);
- note_stores (PATTERN (insn), mark_reg, born);
- AND_REG_SET (born, regs);
-
- /* Regs born here were not live before this insn. */
- AND_COMPL_REG_SET (live, born);
-
- /* For every reg born here, add a conflict with every other
- reg live coming into this insn. */
- EXECUTE_IF_SET_IN_REG_SET
- (born, FIRST_PSEUDO_REGISTER, born_reg, rsi)
- {
- reg_set_iterator rsj;
-
- EXECUTE_IF_SET_IN_REG_SET
- (live, FIRST_PSEUDO_REGISTER, live_reg, rsj)
- {
- /* Build the conflict graph in terms of canonical
- regnos. */
- int b = partition_find (p, born_reg);
- int l = partition_find (p, live_reg);
-
- if (b != l)
- conflict_graph_add (graph, b, l);
- }
- }
-
- /* Morgan's algorithm checks the operands of the insn
- and adds them to the set of live regs. Instead, we
- use death information added by life analysis. Regs
- dead after this instruction were live before it. */
- for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
- if (REG_NOTE_KIND (link) == REG_DEAD)
- {
- unsigned int regno = REGNO (XEXP (link, 0));
-
- if (REGNO_REG_SET_P (regs, regno))
- SET_REGNO_REG_SET (live, regno);
- }
- }
- }
- }
-
- FREE_REG_SET (live);
- FREE_REG_SET (born);
-
- return graph;
-}