From cd73b6174b093b75f581c3310bf784bed7c74c1f Mon Sep 17 00:00:00 2001
From: Jason Ekstrand <jason@jlekstrand.net>
Date: Mon, 6 May 2019 11:17:40 -0500
Subject: [PATCH] nir/lower_to_source_mods: Stop turning add, sat, and neg into
 mov

Reviewed-by: Kristian H. Kristensen <hoegsberg@google.com>
Acked-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
---
 src/compiler/nir/nir_lower_to_source_mods.c | 53 +++++----------------
 src/compiler/nir/nir_validate.c             |  6 +++
 2 files changed, 19 insertions(+), 40 deletions(-)

diff --git a/src/compiler/nir/nir_lower_to_source_mods.c b/src/compiler/nir/nir_lower_to_source_mods.c
index 3315a18670b..63ef4043fe2 100644
--- a/src/compiler/nir/nir_lower_to_source_mods.c
+++ b/src/compiler/nir/nir_lower_to_source_mods.c
@@ -78,13 +78,13 @@ nir_lower_to_source_mods_block(nir_block *block,
          case nir_type_float:
             if (!(options & nir_lower_float_source_mods))
                continue;
-            if (parent->op != nir_op_fmov)
+            if (parent->op != nir_op_fabs && parent->op != nir_op_fneg)
                continue;
             break;
          case nir_type_int:
             if (!(options & nir_lower_int_source_mods))
                continue;
-            if (parent->op != nir_op_imov)
+            if (parent->op != nir_op_iabs && parent->op != nir_op_ineg)
                continue;
             break;
          default:
@@ -98,10 +98,19 @@ nir_lower_to_source_mods_block(nir_block *block,
          if (!parent->src[0].src.is_ssa)
             continue;
 
-         if (!lower_abs && parent->src[0].abs)
+         if (!lower_abs && (parent->op == nir_op_fabs &&
+                            parent->op == nir_op_iabs))
             continue;
 
          nir_instr_rewrite_src(instr, &alu->src[i].src, parent->src[0].src);
+
+         /* Apply any modifiers that come from the parent opcode */
+         if (parent->op == nir_op_fneg || parent->op == nir_op_ineg)
+            alu_src_consume_negate(&alu->src[i]);
+         if (parent->op == nir_op_fabs || parent->op == nir_op_iabs)
+            alu_src_consume_abs(&alu->src[i]);
+
+         /* Apply modifiers from the parent source */
          if (parent->src[0].negate)
             alu_src_consume_negate(&alu->src[i]);
          if (parent->src[0].abs)
@@ -120,41 +129,6 @@ nir_lower_to_source_mods_block(nir_block *block,
          progress = true;
       }
 
-      if (options & nir_lower_float_source_mods) {
-         switch (alu->op) {
-         case nir_op_fsat:
-            alu->op = nir_op_fmov;
-            alu->dest.saturate = true;
-            break;
-         case nir_op_fneg:
-            alu->op = nir_op_fmov;
-            alu->src[0].negate = !alu->src[0].negate;
-            break;
-         case nir_op_fabs:
-            alu->op = nir_op_fmov;
-            alu->src[0].abs = true;
-            alu->src[0].negate = false;
-            break;
-         default:
-            break;
-         }
-      }
-
-      if (options & nir_lower_int_source_mods) {
-         switch (alu->op) {
-         case nir_op_ineg:
-            alu->op = nir_op_imov;
-            alu->src[0].negate = !alu->src[0].negate;
-            break;
-         case nir_op_iabs:
-            alu->op = nir_op_imov;
-            alu->src[0].abs = true;
-            alu->src[0].negate = false;
-            break;
-         default:
-            break;
-         }
-      }
       /* We've covered sources.  Now we're going to try and saturate the
        * destination if we can.
        */
@@ -188,8 +162,7 @@ nir_lower_to_source_mods_block(nir_block *block,
             continue;
          }
 
-         if (child_alu->op != nir_op_fsat &&
-             !(child_alu->op == nir_op_fmov && child_alu->dest.saturate)) {
+         if (child_alu->op != nir_op_fsat) {
             all_children_are_sat = false;
             continue;
          }
diff --git a/src/compiler/nir/nir_validate.c b/src/compiler/nir/nir_validate.c
index b087b0da12d..30c4a9f5c62 100644
--- a/src/compiler/nir/nir_validate.c
+++ b/src/compiler/nir/nir_validate.c
@@ -217,6 +217,9 @@ validate_alu_src(nir_alu_instr *instr, unsigned index, validate_state *state)
 {
    nir_alu_src *src = &instr->src[index];
 
+   if (instr->op == nir_op_fmov || instr->op == nir_op_imov)
+      assert(!src->abs && !src->negate);
+
    unsigned num_components = nir_src_num_components(src->src);
    for (unsigned i = 0; i < NIR_MAX_VEC_COMPONENTS; i++) {
       validate_assert(state, src->swizzle[i] < NIR_MAX_VEC_COMPONENTS);
@@ -319,6 +322,9 @@ validate_alu_dest(nir_alu_instr *instr, validate_state *state)
 {
    nir_alu_dest *dest = &instr->dest;
 
+   if (instr->op == nir_op_fmov || instr->op == nir_op_imov)
+      assert(!dest->saturate);
+
    unsigned dest_size = nir_dest_num_components(dest->dest);
    /*
     * validate that the instruction doesn't write to components not in the