[Mesa-dev] [PATCH 3/5] i965/vs: Add src_reg::negative_equals method

[Ian Romanick]

From: Ian Romanick <ian.d.romanick at intel.com>

This method is similar to the existing ::equals method.  Instead of
testing that two src_regs are equal to each other, it tests that one is
the negation of the other.

Signed-off-by: Ian Romanick <ian.d.romanick at intel.com>
---
 src/mesa/drivers/dri/i965/brw_ir_vec4.h |  1 +
 src/mesa/drivers/dri/i965/brw_vec4.cpp  | 43 +++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_ir_vec4.h b/src/mesa/drivers/dri/i965/brw_ir_vec4.h
index d3bd64d..449795a 100644
--- a/src/mesa/drivers/dri/i965/brw_ir_vec4.h
+++ b/src/mesa/drivers/dri/i965/brw_ir_vec4.h
@@ -49,6 +49,7 @@ public:
    src_reg(struct brw_reg reg);
 
    bool equals(const src_reg &r) const;
+   bool negative_equals(const src_reg &r) const;
 
    src_reg(class vec4_visitor *v, const struct glsl_type *type);
    src_reg(class vec4_visitor *v, const struct glsl_type *type, int size);
diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp b/src/mesa/drivers/dri/i965/brw_vec4.cpp
index ef2fd40..d5286c2 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
@@ -328,6 +328,49 @@ src_reg::equals(const src_reg &r) const
 }
 
 bool
+src_reg::negative_equals(const src_reg &r) const
+{
+   if (file != r.file)
+      return false;
+
+   if (file == IMM) {
+      if (!(reg == r.reg &&
+            reg_offset == r.reg_offset &&
+            type == r.type &&
+            negate == r.negate &&
+            abs == r.abs &&
+            swizzle == r.swizzle &&
+            !reladdr && !r.reladdr))
+         return false;
+
+      switch (fixed_hw_reg.type) {
+      case BRW_REGISTER_TYPE_F:
+         return memcmp(&fixed_hw_reg, &r.fixed_hw_reg,
+                       sizeof(fixed_hw_reg) - sizeof(fixed_hw_reg.dw1)) == 0 &&
+                fixed_hw_reg.dw1.f == -r.fixed_hw_reg.dw1.f;
+
+      case BRW_REGISTER_TYPE_D:
+         return memcmp(&fixed_hw_reg, &r.fixed_hw_reg,
+                       sizeof(fixed_hw_reg) - sizeof(fixed_hw_reg.dw1)) == 0 &&
+                fixed_hw_reg.dw1.d == -r.fixed_hw_reg.dw1.d;
+
+      default:
+         return false;
+      }
+   } else {
+      return reg == r.reg &&
+             reg_offset == r.reg_offset &&
+             type == r.type &&
+             negate != r.negate &&
+             abs == r.abs &&
+             swizzle == r.swizzle &&
+             !reladdr && !r.reladdr &&
+             memcmp(&fixed_hw_reg, &r.fixed_hw_reg,
+                    sizeof(fixed_hw_reg)) == 0;
+   }
+}
+
+bool
 vec4_visitor::opt_vector_float()
 {
    bool progress = false;
-- 
2.1.0