Attachment 48788 Details for Bug 36669 – Proposed fix

[patch] Proposed fix

bug_36669.patch (text/plain), 2.74 KB, created by Paul Berry on 2011-07-05 14:38:41 UTC

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Creator: Paul Berry

Created: 2011-07-05 14:38:41 UTC

Size: 2.74 KB

patch

obsolete

>diff --git a/src/glsl/lower_jumps.cpp b/src/glsl/lower_jumps.cpp
>index dd2601d..b31fea8 100644
>--- a/src/glsl/lower_jumps.cpp
>+++ b/src/glsl/lower_jumps.cpp
>@@ -146,16 +146,17 @@ struct function_record
>    ir_function_signature* signature;
>    ir_variable* return_flag; /* used to break out of all loops and then jump to the return instruction */
>    ir_variable* return_value;
>-   bool is_main;
>+   bool lower_return;
>    unsigned nesting_depth;
> 
>-   function_record(ir_function_signature* p_signature = 0)
>+   function_record(ir_function_signature* p_signature = 0,
>+                   bool lower_return = false)
>    {
>       this->signature = p_signature;
>       this->return_flag = 0;
>       this->return_value = 0;
>       this->nesting_depth = 0;
>-      this->is_main = this->signature && (strcmp(this->signature->function_name(), "main") == 0);
>+      this->lower_return = lower_return;
>    }
> 
>    ir_variable* get_return_flag()
>@@ -274,10 +275,8 @@ struct ir_lower_jumps_visitor : public ir_control_flow_visitor {
>          /* never lower return at the end of a this->function */
>          if(this->function.nesting_depth == 0 && ir->get_next()->is_tail_sentinel())
>             lower = false;
>-         else if (this->function.is_main)
>-            lower = lower_main_return;
>          else
>-            lower = lower_sub_return;
>+            lower = this->function.lower_return;
>          break;
>       }
>       return lower;
>@@ -530,14 +529,35 @@ lower_continue:
>       assert(!this->function.signature);
>       assert(!this->loop.loop);
> 
>+      bool lower_return;
>+      if (strcmp(ir->function_name(), "main") == 0)
>+         lower_return = lower_main_return;
>+      else
>+         lower_return = lower_sub_return;
>+
>       function_record saved_function = this->function;
>       loop_record saved_loop = this->loop;
>-      this->function = function_record(ir);
>+      this->function = function_record(ir, lower_return);
>       this->loop = loop_record(ir);
> 
>       assert(!this->loop.loop);
>       visit_block(&ir->body);
> 
>+      /* If the body ended in an unconditional return of non-void,
>+       * then we don't need to lower it because an unconditional
>+       * return of non-void at the end of a function is what returns
>+       * get lowered to.
>+       *
>+       * If the body ended in a return of void, eliminate it because
>+       * it is redundant.
>+       */
>+      if (ir->return_type->is_void() &&
>+          get_jump_strength((ir_instruction *) ir->body.get_tail())) {
>+         ir_jump *jump = (ir_jump *) ir->body.get_tail();
>+         assert (jump->ir_type == ir_type_return);
>+         jump->remove();
>+      }
>+
>       if(this->function.return_value)
>          ir->body.push_tail(new(ir) ir_return(new (ir) ir_dereference_variable(this->function.return_value)));
>

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Attachments on bug 36669: 46150 | 48788

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