i965: Rewrite disassembly annotation code

The old code used an array to store each "instruction group" (the new,
better name than the old overloaded "annotation"), and required a
memmove() to shift elements over in the array when we needed to split a
group so that we could add an error message. This was confusing and
difficult to get right, not the least of which was  because the array
has a tail sentinel not included in .ann_count.

Instead use a linked list, a data structure made for efficient
insertion.

Acked-by: Samuel Iglesias Gonsálvez <[email protected]>
Reviewed-by: Kenneth Graunke <[email protected]>

1 files changed, 16 insertions, 10 deletions

diff --git a/src/intel/compiler/brw_eu_compact.c b/src/intel/compiler/brw_eu_compact.c
index a9da46957a5..d2edb5586c2 100644
--- a/src/intel/compiler/brw_eu_compact.c
+++ b/src/intel/compiler/brw_eu_compact.c
@@ -1486,7 +1486,7 @@ brw_init_compaction_tables(const struct gen_device_info *devinfo)
 
 void
 brw_compact_instructions(struct brw_codegen *p, int start_offset,
-                         int num_annotations, struct annotation *annotation)
+                         struct disasm_info *disasm)
 {
    if (unlikely(INTEL_DEBUG & DEBUG_NO_COMPACTION))
       return;
@@ -1501,7 +1501,7 @@ brw_compact_instructions(struct brw_codegen *p, int start_offset,
    /* For an instruction at byte offset 8*i after compaction, this was its IP
     * (in 16-byte units) before compaction.
     */
-   int old_ip[(p->next_insn_offset - start_offset) / sizeof(brw_compact_inst)];
+   int old_ip[(p->next_insn_offset - start_offset) / sizeof(brw_compact_inst) + 1];
 
    if (devinfo->gen == 4 && !devinfo->is_g4x)
       return;
@@ -1556,6 +1556,12 @@ brw_compact_instructions(struct brw_codegen *p, int start_offset,
       }
    }
 
+   /* Add an entry for the ending offset of the program. This greatly
+    * simplifies the linked list walk at the end of the function.
+    */
+   old_ip[offset / sizeof(brw_compact_inst)] =
+      (p->next_insn_offset - start_offset) / sizeof(brw_inst);
+
    /* Fix up control flow offsets. */
    p->next_insn_offset = start_offset + offset;
    for (offset = 0; offset < p->next_insn_offset - start_offset;
@@ -1651,21 +1657,21 @@ brw_compact_instructions(struct brw_codegen *p, int start_offset,
    }
    p->nr_insn = p->next_insn_offset / sizeof(brw_inst);
 
-   /* Update the instruction offsets for each annotation. */
-   if (annotation) {
-      for (int offset = 0, i = 0; i < num_annotations; i++) {
+   /* Update the instruction offsets for each group. */
+   if (disasm) {
+      int offset = 0;
+
+      foreach_list_typed(struct inst_group, group, link, &disasm->group_list) {
          while (start_offset + old_ip[offset / sizeof(brw_compact_inst)] *
-                sizeof(brw_inst) != annotation[i].offset) {
+                sizeof(brw_inst) != group->offset) {
             assert(start_offset + old_ip[offset / sizeof(brw_compact_inst)] *
-                   sizeof(brw_inst) < annotation[i].offset);
+                   sizeof(brw_inst) < group->offset);
             offset = next_offset(devinfo, store, offset);
          }
 
-         annotation[i].offset = start_offset + offset;
+         group->offset = start_offset + offset;
 
          offset = next_offset(devinfo, store, offset);
       }
-
-      annotation[num_annotations].offset = p->next_insn_offset;
    }
 }