glsl: Remove const decoration from inlined function parameters

The constness of the function parameter gets inlined with the rest of
the function.  However, there is also an assignment to the parameter.
If this occurs inside a loop the loop analysis code will get confused
by the assignment to a read-only variable.

Fixes bugzilla #30552.

NOTE: this is a candidate for the 7.9 branch.

diff --git a/src/glsl/ir_function_inlining.cpp b/src/glsl/ir_function_inlining.cpp
index 874602c84f291f095828c615c0d45baf5dc0dfb9..147c1824c1a06f5a450e92949336b35193e9e9c5 100644 (file)
--- a/src/glsl/ir_function_inlining.cpp
+++ b/src/glsl/ir_function_inlining.cpp
@@ -153,6 +153,13 @@ ir_call::generate_inline(ir_instruction *next_ir)
       } else {
         parameters[i] = sig_param->clone(ctx, ht);
         parameters[i]->mode = ir_var_auto;
+
+        /* Remove the read-only decoration becuase we're going to write
+         * directly to this variable.  If the cloned variable is left
+         * read-only and the inlined function is inside a loop, the loop
+         * analysis code will get confused.
+         */
+        parameters[i]->read_only = false;
         next_ir->insert_before(parameters[i]);
       }