From: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Date: Fri, 26 Jul 2019 16:20:52 +0000 (-0700)
Subject: pan/midgard: Add mir_is_written_before helper
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=481447cb00821fdc81d7ab328a8c70a02546cf78;p=mesa.git

pan/midgard: Add mir_is_written_before helper

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
---

diff --git a/src/panfrost/midgard/compiler.h b/src/panfrost/midgard/compiler.h
index f3fd92ad50b..528dfacdc3b 100644
--- a/src/panfrost/midgard/compiler.h
+++ b/src/panfrost/midgard/compiler.h
@@ -381,6 +381,7 @@ void mir_rewrite_index_src_tag(compiler_context *ctx, unsigned old, unsigned new
 bool mir_single_use(compiler_context *ctx, unsigned value);
 bool mir_special_index(compiler_context *ctx, unsigned idx);
 unsigned mir_use_count(compiler_context *ctx, unsigned value);
+bool mir_is_written_before(compiler_context *ctx, midgard_instruction *ins, unsigned node);
 
 /* MIR printing */
 
diff --git a/src/panfrost/midgard/mir.c b/src/panfrost/midgard/mir.c
index d8e52982b68..61427e7c3d5 100644
--- a/src/panfrost/midgard/mir.c
+++ b/src/panfrost/midgard/mir.c
@@ -175,3 +175,22 @@ mir_special_index(compiler_context *ctx, unsigned idx)
 
         return false;
 }
+
+/* Is a node written before a given instruction? */
+
+bool
+mir_is_written_before(compiler_context *ctx, midgard_instruction *ins, unsigned node)
+{
+        if ((node < 0) || (node >= SSA_FIXED_MINIMUM))
+                return true;
+
+        mir_foreach_instr_global(ctx, q) {
+                if (q == ins)
+                        break;
+
+                if (q->ssa_args.dest == node)
+                        return true;
+        }
+
+        return false;
+}