media-libs/mesa/files/7.11_p2-Revert-i965-Avoid-generating-MOVs-for-most-ir_assign.patch

From 2d44f205007e0928ebf9a9b914c9308ae3dd2a12 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?St=C3=A9phane=20Marchesin?= <marcheu@chromium.org>
Date: Wed, 19 Oct 2011 19:26:08 -0700
Subject: [PATCH] Revert "i965: Avoid generating MOVs for most ir_assignment
 handling."

This reverts commit dc7f449d1ac53a66e6efb56ccf2a5953418a26ca.
---
 src/mesa/drivers/dri/i965/brw_fs.h           |    5 ---
 src/mesa/drivers/dri/i965/brw_fs_visitor.cpp |   43 --------------------------
 2 files changed, 0 insertions(+), 48 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
index f344330..435ac98 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.h
+++ b/src/mesa/drivers/dri/i965/brw_fs.h
@@ -528,11 +528,6 @@ public:
 
    void emit_color_write(int index, int first_color_mrf, fs_reg color);
    void emit_fb_writes();
-   bool try_rewrite_rhs_to_dst(ir_assignment *ir,
-			       fs_reg dst,
-			       fs_reg src,
-			       fs_inst *pre_rhs_inst,
-			       fs_inst *last_rhs_inst);
    void emit_assignment_writes(fs_reg &l, fs_reg &r,
 			       const glsl_type *type, bool predicated);
 
diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index e523ae7..d328454 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -505,42 +505,6 @@ fs_visitor::emit_assignment_writes(fs_reg &l, fs_reg &r,
    }
 }
 
-/* If the RHS processing resulted in an instruction generating a
- * temporary value, and it would be easy to rewrite the instruction to
- * generate its result right into the LHS instead, do so.  This ends
- * up reliably removing instructions where it can be tricky to do so
- * later without real UD chain information.
- */
-bool
-fs_visitor::try_rewrite_rhs_to_dst(ir_assignment *ir,
-                                   fs_reg dst,
-                                   fs_reg src,
-                                   fs_inst *pre_rhs_inst,
-                                   fs_inst *last_rhs_inst)
-{
-   if (pre_rhs_inst == last_rhs_inst)
-      return false; /* No instructions generated to work with. */
-
-   /* Only attempt if we're doing a direct assignment. */
-   if (ir->condition ||
-       !(ir->lhs->type->is_scalar() ||
-        (ir->lhs->type->is_vector() &&
-         ir->write_mask == (1 << ir->lhs->type->vector_elements) - 1)))
-      return false;
-
-   /* Make sure the last instruction generated our source reg. */
-   if (last_rhs_inst->predicated ||
-       last_rhs_inst->force_uncompressed ||
-       last_rhs_inst->force_sechalf ||
-       !src.equals(&last_rhs_inst->dst))
-      return false;
-
-   /* Success!  Rewrite the instruction. */
-   last_rhs_inst->dst = dst;
-
-   return true;
-}
-
 void
 fs_visitor::visit(ir_assignment *ir)
 {
@@ -551,19 +515,12 @@ fs_visitor::visit(ir_assignment *ir)
    ir->lhs->accept(this);
    l = this->result;
 
-   fs_inst *pre_rhs_inst = (fs_inst *) this->instructions.get_tail();
-
    ir->rhs->accept(this);
    r = this->result;
 
-   fs_inst *last_rhs_inst = (fs_inst *) this->instructions.get_tail();
-
    assert(l.file != BAD_FILE);
    assert(r.file != BAD_FILE);
 
-   if (try_rewrite_rhs_to_dst(ir, l, r, pre_rhs_inst, last_rhs_inst))
-      return;
-
    if (ir->condition) {
       emit_bool_to_cond_code(ir->condition);
    }
-- 
1.7.5.3.367.ga9930