| From 0d50be1a1ff4264bd48f93b0e85544ace1807c0a Mon Sep 17 00:00:00 2001 |
| From: Chris Wolfe <cwolfe@chromium.org> |
| Date: Tue, 7 Aug 2012 18:57:05 -0400 |
| Subject: [PATCH] glsl: Restrict opt_dead_code_local to variable assignment |
| |
| Temporary fix to Chrome OS bug <http://crosbug.com/32326> |
| |
| Change-Id: I4ca51603da18e3156f90ed77490902b3f8229f5c |
| --- |
| src/glsl/opt_dead_code_local.cpp | 12 +++++++++++- |
| 1 files changed, 11 insertions(+), 1 deletions(-) |
| |
| diff --git a/src/glsl/opt_dead_code_local.cpp b/src/glsl/opt_dead_code_local.cpp |
| index 4af78a7..0e3a7f4 100644 |
| --- a/src/glsl/opt_dead_code_local.cpp |
| +++ b/src/glsl/opt_dead_code_local.cpp |
| @@ -252,10 +252,20 @@ process_assignment(void *ctx, ir_assignment *ir, exec_list *assignments) |
| } |
| } |
| |
| + if (ir->lhs->as_dereference_variable() == NULL) { |
| + /* HACK: Chrome has encountered bugs when this optimization processes |
| + * array elements in the lhs. For example: |
| + * vec4 tmp; tmp[3] = 1.0; |
| + * is incorrectly recorded as writing to only the (x) element, and will |
| + * be killed if a later statement replaces (x). To sidestep this problem |
| + * temporarily, trim only assignments to bare variables. |
| + */ |
| + return progress; |
| + } |
| + |
| /* Add this instruction to the assignment list available to be removed. */ |
| assignment_entry *entry = new(ctx) assignment_entry(var, ir); |
| assignments->push_tail(entry); |
| - |
| if (debug) { |
| printf("add %s\n", var->name); |
| |
| -- |
| 1.7.7.3 |
| |
