X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=src%2Fcompiler%2Fnir%2Fnir_opt_remove_phis.c;h=9efbf422624f10540f38dbb67ec615a1f278ecaa;hb=535251487ba56c4fd98465c4682881c2b9734242;hp=07c575660b49987c2c1a1a35249305df1e09ae71;hpb=b6dc940ec273252678d40707d300851fa1c85ea5;p=mesa.git

diff --git a/src/compiler/nir/nir_opt_remove_phis.c b/src/compiler/nir/nir_opt_remove_phis.c
index 07c575660b4..9efbf422624 100644
--- a/src/compiler/nir/nir_opt_remove_phis.c
+++ b/src/compiler/nir/nir_opt_remove_phis.c
@@ -26,6 +26,27 @@
  */
 
 #include "nir.h"
+#include "nir_builder.h"
+
+static nir_alu_instr *
+get_parent_mov(nir_ssa_def *ssa)
+{
+   if (ssa->parent_instr->type != nir_instr_type_alu)
+      return NULL;
+
+   nir_alu_instr *alu = nir_instr_as_alu(ssa->parent_instr);
+   return (alu->op == nir_op_imov || alu->op == nir_op_fmov) ? alu : NULL;
+}
+
+static bool
+matching_mov(nir_alu_instr *mov1, nir_ssa_def *ssa)
+{
+   if (!mov1)
+      return false;
+
+   nir_alu_instr *mov2 = get_parent_mov(ssa);
+   return mov2 && nir_alu_srcs_equal(mov1, mov2, 0, 0);
+}
 
 /*
  * This is a pass for removing phi nodes that look like:
@@ -43,20 +64,21 @@
  */
 
 static bool
-remove_phis_block(nir_block *block, void *state)
+remove_phis_block(nir_block *block, nir_builder *b)
 {
-   bool *progress = state;
+   bool progress = false;
 
-   nir_foreach_instr_safe(block, instr) {
+   nir_foreach_instr_safe(instr, block) {
       if (instr->type != nir_instr_type_phi)
          break;
 
       nir_phi_instr *phi = nir_instr_as_phi(instr);
 
       nir_ssa_def *def = NULL;
+      nir_alu_instr *mov = NULL;
       bool srcs_same = true;
 
-      nir_foreach_phi_src(phi, src) {
+      nir_foreach_phi_src(src, phi) {
          assert(src->src.is_ssa);
 
          /* For phi nodes at the beginning of loops, we may encounter some
@@ -75,8 +97,9 @@ remove_phis_block(nir_block *block, void *state)
          
          if (def == NULL) {
             def  = src->src.ssa;
+            mov = get_parent_mov(def);
          } else {
-            if (src->src.ssa != def) {
+            if (src->src.ssa != def && !matching_mov(mov, src->src.ssa)) {
                srcs_same = false;
                break;
             }
@@ -91,26 +114,49 @@ remove_phis_block(nir_block *block, void *state)
        */
       assert(def != NULL);
 
+      if (mov) {
+         /* If the sources were all movs from the same source with the same
+          * swizzle, then we can't just pick a random move because it may not
+          * dominate the phi node. Instead, we need to emit our own move after
+          * the phi which uses the shared source, and rewrite uses of the phi
+          * to use the move instead. This is ok, because while the movs may
+          * not all dominate the phi node, their shared source does.
+          */
+
+         b->cursor = nir_after_phis(block);
+         def = mov->op == nir_op_imov ?
+            nir_imov_alu(b, mov->src[0], def->num_components) :
+            nir_fmov_alu(b, mov->src[0], def->num_components);
+      }
+
       assert(phi->dest.is_ssa);
       nir_ssa_def_rewrite_uses(&phi->dest.ssa, nir_src_for_ssa(def));
       nir_instr_remove(instr);
 
-      *progress = true;
+      progress = true;
    }
 
-   return true;
+   return progress;
 }
 
 static bool
-remove_phis_impl(nir_function_impl *impl)
+nir_opt_remove_phis_impl(nir_function_impl *impl)
 {
    bool progress = false;
+   nir_builder bld;
+   nir_builder_init(&bld, impl);
 
-   nir_foreach_block_call(impl, remove_phis_block, &progress);
+   nir_foreach_block(block, impl) {
+      progress |= remove_phis_block(block, &bld);
+   }
 
    if (progress) {
       nir_metadata_preserve(impl, nir_metadata_block_index |
                                   nir_metadata_dominance);
+   } else {
+#ifndef NDEBUG
+      impl->valid_metadata &= ~nir_metadata_not_properly_reset;
+#endif
    }
 
    return progress;
@@ -121,9 +167,9 @@ nir_opt_remove_phis(nir_shader *shader)
 {
    bool progress = false;
 
-   nir_foreach_function(shader, function)
+   nir_foreach_function(function, shader)
       if (function->impl)
-         progress = remove_phis_impl(function->impl) || progress;
+         progress = nir_opt_remove_phis_impl(function->impl) || progress;
 
    return progress;
 }