From 240b2f966f104a1a818863a6a33121dd738ac5d5 Mon Sep 17 00:00:00 2001
From: Nikolay Sivov <nsivov@codeweavers.com>
Date: Sun, 5 Feb 2023 02:30:36 +0300
Subject: [PATCH] vkd3d-shader/hlsl: Support abs() for SM1.

---
 libs/vkd3d-shader/hlsl_codegen.c | 30 ++++++++++++++++++++++++++++++
 libs/vkd3d-shader/hlsl_sm1.c     |  4 ++++
 2 files changed, 34 insertions(+)

diff --git a/libs/vkd3d-shader/hlsl_codegen.c b/libs/vkd3d-shader/hlsl_codegen.c
index 7c95ebd1..5fd754e5 100644
--- a/libs/vkd3d-shader/hlsl_codegen.c
+++ b/libs/vkd3d-shader/hlsl_codegen.c
@@ -1591,6 +1591,31 @@ static bool lower_dot(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr, void *co
     return true;
 }
 
+/* Lower ABS to MAX */
+static bool lower_abs(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr, void *context)
+{
+    struct hlsl_ir_node *arg, *neg, *replacement;
+    struct hlsl_ir_expr *expr;
+
+    if (instr->type != HLSL_IR_EXPR)
+        return false;
+    expr = hlsl_ir_expr(instr);
+    arg = expr->operands[0].node;
+    if (expr->op != HLSL_OP1_ABS)
+        return false;
+
+    if (!(neg = hlsl_new_unary_expr(ctx, HLSL_OP1_NEG, arg, instr->loc)))
+        return false;
+    list_add_before(&instr->entry, &neg->entry);
+
+    if (!(replacement = hlsl_new_binary_expr(ctx, HLSL_OP2_MAX, neg, arg)))
+        return false;
+    list_add_before(&instr->entry, &replacement->entry);
+
+    hlsl_replace_node(instr, replacement);
+    return true;
+}
+
 static bool lower_casts_to_bool(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr, void *context)
 {
     struct hlsl_type *type = instr->data_type, *arg_type;
@@ -3009,6 +3034,11 @@ int hlsl_emit_bytecode(struct hlsl_ctx *ctx, struct hlsl_ir_function_decl *entry
         transform_ir(ctx, lower_dot, body, NULL);
     }
 
+    if (profile->major_version < 2)
+    {
+        transform_ir(ctx, lower_abs, body, NULL);
+    }
+
     transform_ir(ctx, validate_static_object_references, body, NULL);
 
     /* TODO: move forward, remove when no longer needed */
diff --git a/libs/vkd3d-shader/hlsl_sm1.c b/libs/vkd3d-shader/hlsl_sm1.c
index 34bead54..41b111a5 100644
--- a/libs/vkd3d-shader/hlsl_sm1.c
+++ b/libs/vkd3d-shader/hlsl_sm1.c
@@ -682,6 +682,10 @@ static void write_sm1_expr(struct hlsl_ctx *ctx, struct vkd3d_bytecode_buffer *b
 
     switch (expr->op)
     {
+        case HLSL_OP1_ABS:
+            write_sm1_unary_op(ctx, buffer, D3DSIO_ABS, &instr->reg, &arg1->reg, 0, 0);
+            break;
+
         case HLSL_OP1_EXP2:
             write_sm1_per_component_unary_op(ctx, buffer, instr, D3DSIO_EXP);
             break;