glsl2: Don't dead-code eliminate a call where the return value is unused.

This showed up since the disabling of inlining at compile time, which
I apparently didn't regenerate piglit summary for.

Fixes:
glsl-deadcode-call.

diff --git a/src/glsl/ir.h b/src/glsl/ir.h
index f58602515efce815bffb3893cf8f3e89ab9f5e05..ef8339ce1997ab69a827cdd0513a7e550a824dd5 100644 (file)
--- a/src/glsl/ir.h
+++ b/src/glsl/ir.h
@@ -1389,4 +1389,7 @@ extern void
 import_prototypes(const exec_list *source, exec_list *dest,
                  class glsl_symbol_table *symbols, void *mem_ctx);
 
+extern bool
+ir_has_call(ir_instruction *ir);
+
 #endif /* IR_H */

diff --git a/src/glsl/ir_basic_block.cpp b/src/glsl/ir_basic_block.cpp
index f9953ea42dafa47b89276472b7990b4d8025b918..a8338259620501dd782e26115658c25e70b5e2c8 100644 (file)
--- a/src/glsl/ir_basic_block.cpp
+++ b/src/glsl/ir_basic_block.cpp
@@ -49,6 +49,14 @@ public:
    bool has_call;
 };
 
+bool
+ir_has_call(ir_instruction *ir)
+{
+   ir_has_call_visitor v;
+   ir->accept(&v);
+   return v.has_call;
+}
+
 /**
  * Calls a user function for every basic block in the instruction stream.
  *
@@ -115,8 +123,6 @@ void call_for_basic_blocks(exec_list *instructions,
            call_for_basic_blocks(&ir_sig->body, callback, data);
         }
       } else if (ir->as_assignment()) {
-        ir_has_call_visitor v;
-
         /* If there's a call in the expression tree being assigned,
          * then that ends the BB too.
          *
@@ -130,8 +136,7 @@ void call_for_basic_blocks(exec_list *instructions,
          * expression flattener may be useful before using the basic
          * block finder to get more maximal basic blocks out.
          */
-        ir->accept(&v);
-        if (v.has_call) {
+        if (ir_has_call(ir)) {
            callback(leader, ir, data);
            leader = NULL;
         }

diff --git a/src/glsl/ir_dead_code.cpp b/src/glsl/ir_dead_code.cpp
index a8d264f39a992fde7dfa966865440f6bbb8e9635..87988871c7ed62d722503babb9ee453b96900c73 100644 (file)
--- a/src/glsl/ir_dead_code.cpp
+++ b/src/glsl/ir_dead_code.cpp
@@ -78,7 +78,8 @@ do_dead_code(exec_list *instructions)
          * Don't do so if it's a shader output, though.
          */
         if (entry->var->mode != ir_var_out &&
-            entry->var->mode != ir_var_inout) {
+            entry->var->mode != ir_var_inout &&
+            !ir_has_call(entry->assign)) {
            entry->assign->remove();
            progress = true;
 

diff --git a/src/glsl/ir_dead_code_local.cpp b/src/glsl/ir_dead_code_local.cpp
index b22cc558df6392f88e6beccebcc135b4e3ddf52b..4bbedf0ff946e50c222c6aa1d69a228384c3e3e5 100644 (file)
--- a/src/glsl/ir_dead_code_local.cpp
+++ b/src/glsl/ir_dead_code_local.cpp
@@ -156,7 +156,12 @@ process_assignment(void *ctx, ir_assignment *ir, exec_list *assignments)
       }
    }
 
-   /* Add this instruction to the assignment list. */
+   /* Add this instruction to the assignment list available to be removed.
+    * But not if the assignment has other side effects.
+    */
+   if (ir_has_call(ir))
+      return progress;
+
    assignment_entry *entry = new(ctx) assignment_entry(var, ir);
    assignments->push_tail(entry);