i965/fs: Add fs_reg::is_zero() and is_one(); use for opt_algebraic().

These helper macros save you from writing nasty expressions like:

   if ((inst->src[1].type == BRW_REGISTER_TYPE_F &&
         inst->src[1].imm.f == 1.0) ||
        ((inst->src[1].type == BRW_REGISTER_TYPE_D ||
          inst->src[1].type == BRW_REGISTER_TYPE_UD) &&
         inst->src[1].imm.u == 1)) {

Instead, you simply get to write inst->src[1].is_one().  Simple.
Also, this makes the FS backend match the VS backend (which has these).

This patch also converts opt_algebraic to use the new helper functions.
As a consequence, it will now also optimize integer-typed expressions.

Reviewed-by: Eric Anholt <eric@anholt.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
index a0ed743486b..86c33bc8b0f 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.h
+++ b/src/mesa/drivers/dri/i965/brw_fs.h
@@ -91,6 +91,8 @@ public:
    fs_reg(class fs_visitor *v, const struct glsl_type *type);
 
    bool equals(const fs_reg &r) const;
+   bool is_zero() const;
+   bool is_one() const;
 
    /** Register file: ARF, GRF, MRF, IMM. */
    enum register_file file;