Nikolay Sivov : vkd3d-shader/hlsl: Handle round() for SM1.

[Alexandre Julliard]

Module: vkd3d
Branch: master
Commit: eb71c5f20dd0a141b35f04887cc81ff88b9db6ba
URL:    https://gitlab.winehq.org/wine/vkd3d/-/commit/eb71c5f20dd0a141b35f04887cc81f...

Author: Nikolay Sivov 
Date:   Thu Mar 16 21:14:12 2023 +0100

vkd3d-shader/hlsl: Handle round() for SM1.

---

libs/vkd3d-shader/hlsl_codegen.c | 46 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/libs/vkd3d-shader/hlsl_codegen.c b/libs/vkd3d-shader/hlsl_codegen.c
index 75ac2e64..6c529f19 100644
--- a/libs/vkd3d-shader/hlsl_codegen.c
+++ b/libs/vkd3d-shader/hlsl_codegen.c
@@ -1848,6 +1848,51 @@ static bool lower_abs(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr, void *co
     return true;
 }

+/* Lower ROUND using FRC, ROUND(x) -> ((x + 0.5) - FRC(x + 0.5)). */
+static bool lower_round(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr, void *context)
+{
+    struct hlsl_ir_node *arg, *neg, *sum, *frc, *replacement;
+    struct hlsl_type *type = instr->data_type;
+    unsigned int i, component_count;
+    struct hlsl_ir_constant *half;
+    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_ROUND)
+        return false;
+
+    if (!(half = hlsl_new_constant(ctx, type, &expr->node.loc)))
+        return false;
+
+    component_count = hlsl_type_component_count(type);
+    for (i = 0; i < component_count; ++i)
+        half->value[i].f = 0.5f;
+    list_add_before(&instr->entry, &half->node.entry);
+
+    if (!(sum = hlsl_new_binary_expr(ctx, HLSL_OP2_ADD, arg, &half->node)))
+        return false;
+    list_add_before(&instr->entry, &sum->entry);
+
+    if (!(frc = hlsl_new_unary_expr(ctx, HLSL_OP1_FRACT, sum, instr->loc)))
+        return false;
+    list_add_before(&instr->entry, &frc->entry);
+
+    if (!(neg = hlsl_new_unary_expr(ctx, HLSL_OP1_NEG, frc, instr->loc)))
+        return false;
+    list_add_before(&instr->entry, &neg->entry);
+
+    if (!(replacement = hlsl_new_binary_expr(ctx, HLSL_OP2_ADD, sum, neg)))
+        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;
@@ -3305,6 +3350,7 @@ int hlsl_emit_bytecode(struct hlsl_ctx *ctx, struct hlsl_ir_function_decl *entry
         transform_ir(ctx, lower_division, body, NULL);
         transform_ir(ctx, lower_sqrt, body, NULL);
         transform_ir(ctx, lower_dot, body, NULL);
+        transform_ir(ctx, lower_round, body, NULL);
     }

if (profile->major_version < 2)