Mesa (master): intel/isl: Add an isl_color_value_is_zero helper

[Jason Ekstrand]

Module: Mesa
Branch: master
Commit: 4796025ba518baa0e8893337591a3f452a375d94
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=4796025ba518baa0e8893337591a3f452a375d94

Author: Jason Ekstrand <jason.ekstrand at intel.com>
Date:   Mon Feb 12 15:50:12 2018 -0800

intel/isl: Add an isl_color_value_is_zero helper

Cc: mesa-stable at lists.freedesktop.org
Reviewed-by: Nanley Chery <nanley.g.chery at intel.com>

---

 src/intel/isl/isl.c | 20 ++++++++++++++++++++
 src/intel/isl/isl.h |  3 +++
 2 files changed, 23 insertions(+)

diff --git a/src/intel/isl/isl.c b/src/intel/isl/isl.c
index 4dce0596d2..1a32c02818 100644
--- a/src/intel/isl/isl.c
+++ b/src/intel/isl/isl.c
@@ -269,6 +269,26 @@ isl_tiling_get_info(enum isl_tiling tiling,
 }
 
 bool
+isl_color_value_is_zero(union isl_color_value value,
+                        enum isl_format format)
+{
+   const struct isl_format_layout *fmtl = isl_format_get_layout(format);
+
+#define RETURN_FALSE_IF_NOT_0(c, i) \
+   if (fmtl->channels.c.bits && value.u32[i] != 0) \
+      return false
+
+   RETURN_FALSE_IF_NOT_0(r, 0);
+   RETURN_FALSE_IF_NOT_0(g, 1);
+   RETURN_FALSE_IF_NOT_0(b, 2);
+   RETURN_FALSE_IF_NOT_0(a, 3);
+
+#undef RETURN_FALSE_IF_NOT_0
+
+   return true;
+}
+
+bool
 isl_color_value_is_zero_one(union isl_color_value value,
                             enum isl_format format)
 {
diff --git a/src/intel/isl/isl.h b/src/intel/isl/isl.h
index fda2411510..209769a9a9 100644
--- a/src/intel/isl/isl.h
+++ b/src/intel/isl/isl.h
@@ -1692,6 +1692,9 @@ isl_extent4d(uint32_t width, uint32_t height, uint32_t depth,
    return e;
 }
 
+bool isl_color_value_is_zero(union isl_color_value value,
+                             enum isl_format format);
+
 bool isl_color_value_is_zero_one(union isl_color_value value,
                                  enum isl_format format);