[Mesa-dev] [PATCH 4/7] nir/search: Add a swizzle to nir_search_variable and use it for replacements

[Jason Ekstrand]

---
 src/glsl/nir/nir_algebraic.py | 14 ++++++++++++++
 src/glsl/nir/nir_search.c     |  6 +++++-
 src/glsl/nir/nir_search.h     |  7 +++++++
 3 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/src/glsl/nir/nir_algebraic.py b/src/glsl/nir/nir_algebraic.py
index f9b246d..37eb523 100644
--- a/src/glsl/nir/nir_algebraic.py
+++ b/src/glsl/nir/nir_algebraic.py
@@ -28,6 +28,7 @@ import itertools
 import struct
 import sys
 import mako.template
+import re
 
 # Represents a set of variables, each with a unique id
 class VarSet(object):
@@ -60,6 +61,7 @@ static const ${val.c_type} ${val.name} = {
    { ${hex(val)} /* ${val.value} */ },
 % elif isinstance(val, Variable):
    ${val.index}, /* ${val.var_name} */
+   { ${', '.join(str(s) for s in val.swizzle)} },
 % elif isinstance(val, Expression):
    nir_op_${val.opcode},
    { ${', '.join(src.c_ptr for src in val.sources)} },
@@ -106,13 +108,25 @@ class Constant(Value):
       else:
          assert False
 
+_swizzle_re = re.compile(r'(.*)\.([xyzw]{1,4})')
+
 class Variable(Value):
    def __init__(self, val, name, varset):
+      match = _swizzle_re.match(name)
+      if match:
+         name = match.group(1)
+
       Value.__init__(self, name, "variable")
+
       self.var_name = val
       self.index = varset[val]
       self.name = name
 
+      if match:
+         self.swizzle = ['xyzw'.find(s) for s in match.group(2)]
+      else:
+         self.swizzle = range(4)
+
 class Expression(Value):
    def __init__(self, expr, name_base, varset):
       Value.__init__(self, name_base, "expression")
diff --git a/src/glsl/nir/nir_search.c b/src/glsl/nir/nir_search.c
index 4f46cf6..4af34bf 100644
--- a/src/glsl/nir/nir_search.c
+++ b/src/glsl/nir/nir_search.c
@@ -69,6 +69,8 @@ match_value(const nir_search_value *value, nir_alu_instr *instr, unsigned src,
    case nir_search_value_variable: {
       nir_search_variable *var = nir_search_value_as_variable(value);
 
+      assert(memcmp(var->swizzle, identity_swizzle, 4) == 0);
+
       if (state->variables_seen & (1 << var->variable)) {
          if (state->variables[var->variable].ssa != instr->src[src].src.ssa)
             return false;
@@ -242,7 +244,9 @@ construct_value(const nir_search_value *value, nir_alu_type type,
       val.src = nir_src_for_ssa(state->variables[var->variable].ssa);
       val.abs = false;
       val.negate = false;
-      memcpy(val.swizzle, state->variables[var->variable].swizzle, 4);
+
+      for (unsigned i = 0; i < 4; ++i)
+         val.swizzle[i] = state->variables[var->variable].swizzle[var->swizzle[i]];
 
       return val;
    }
diff --git a/src/glsl/nir/nir_search.h b/src/glsl/nir/nir_search.h
index 8ec58b0..8b89dd0 100644
--- a/src/glsl/nir/nir_search.h
+++ b/src/glsl/nir/nir_search.h
@@ -47,6 +47,13 @@ typedef struct {
 
    /** The variable index;  Must be less than NIR_SEARCH_MAX_VARIABLES */
    unsigned variable;
+
+   /** A swizzle value corresponding to nir_alu_src.swizzle
+    *
+    * This is currently only allowed in replacement expressions, not
+    * searches.
+    */
+   uint8_t swizzle[4];
 } nir_search_variable;
 
 typedef struct {
-- 
2.2.1