i965/fs: Avoid constant propagation when the type sizes don't match.

[mesa.git] / src / mesa / drivers / dri / i965 / brw_fs_copy_propagation.cpp

diff --git a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
index ceaaf5f411f3d33355aa8ab35ff00766f32b5158..6aec50617b20a895af22e0c0d1310816617c85c7 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
@@ -538,6 +538,14 @@ fs_visitor::try_constant_propagate(fs_inst *inst, acp_entry *entry)
                                entry->dst, entry->regs_written))
          continue;
 
+      /* If the type sizes don't match each channel of the instruction is
+       * either extracting a portion of the constant (which could be handled
+       * with some effort but the code below doesn't) or reading multiple
+       * channels of the source at once.
+       */
+      if (type_sz(inst->src[i].type) != type_sz(entry->dst.type))
+         continue;
+
       fs_reg val = entry->src;
       val.type = inst->src[i].type;