[PATCH v3 1/3] vkd3d-shader/hlsl: Allow 'break' instructions in loops.

[Nikolay Sivov]

From: Nikolay Sivov

Signed-off-by: Nikolay Sivov 
---
 libs/vkd3d-shader/hlsl.y         | 12 +++++++++++-
 libs/vkd3d-shader/hlsl_codegen.c | 33 ++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/libs/vkd3d-shader/hlsl.y b/libs/vkd3d-shader/hlsl.y
index 0e07fe57..6b010493 100644
--- a/libs/vkd3d-shader/hlsl.y
+++ b/libs/vkd3d-shader/hlsl.y
@@ -5719,7 +5719,17 @@ statement:
     | loop_statement

jump_statement:
-      KW_RETURN expr ';'
+      KW_BREAK ';'
+        {
+            struct hlsl_ir_node *jump;
+
+            if (!($$ = make_empty_list(ctx)))
+                YYABORT;
+            if (!(jump = hlsl_new_jump(ctx, HLSL_IR_JUMP_BREAK, &@1)))
+                YYABORT;
+            list_add_tail($$, &jump->entry);
+        }
+    | KW_RETURN expr ';'
         {
             if (!add_return(ctx, $2, node_from_list($2), &@1))
                 YYABORT;
diff --git a/libs/vkd3d-shader/hlsl_codegen.c b/libs/vkd3d-shader/hlsl_codegen.c
index 765b1907..5c10ec8b 100644
--- a/libs/vkd3d-shader/hlsl_codegen.c
+++ b/libs/vkd3d-shader/hlsl_codegen.c
@@ -3978,6 +3978,37 @@ static bool type_has_object_components(struct hlsl_type *type)
     return false;
 }

+static void validate_flow_control_usage(struct hlsl_ctx *ctx, const struct hlsl_block *block)
+{
+    struct hlsl_ir_node *instr;
+
+    LIST_FOR_EACH_ENTRY(instr, &block->instrs, struct hlsl_ir_node, entry)
+    {
+        if (instr->type == HLSL_IR_LOOP)
+            continue;
+
+        /* TODO: allow breaks in the switch statements. */
+
+        if (instr->type == HLSL_IR_IF)
+        {
+            struct hlsl_ir_if *iff = hlsl_ir_if(instr);
+
+            validate_flow_control_usage(ctx, &iff->then_block);
+            validate_flow_control_usage(ctx, &iff->else_block);
+        }
+        else if (instr->type == HLSL_IR_JUMP)
+        {
+            struct hlsl_ir_jump *jump = hlsl_ir_jump(instr);
+
+            if (jump->type == HLSL_IR_JUMP_BREAK)
+            {
+                hlsl_error(ctx, &instr->loc, VKD3D_SHADER_ERROR_HLSL_INVALID_SYNTAX,
+                        "Flow control instruction "break" can't be used in this context.");
+            }
+        }
+    }
+}
+
 int hlsl_emit_bytecode(struct hlsl_ctx *ctx, struct hlsl_ir_function_decl *entry_func,
         enum vkd3d_shader_target_type target_type, struct vkd3d_shader_code *out)
 {
@@ -4002,6 +4033,8 @@ int hlsl_emit_bytecode(struct hlsl_ctx *ctx, struct hlsl_ir_function_decl *entry
     lower_return(ctx, entry_func, body, false);

while (hlsl_transform_ir(ctx, lower_calls, body, NULL));
+    /* Check that 'break'/'continue' are used in appropriate context. */
+    validate_flow_control_usage(ctx, body);

hlsl_transform_ir(ctx, lower_index_loads, body, NULL);