glsl: Constify ir_instruction::equals

v2: Don't be lazy.  Constify the as_foo functions and use those instead
of ugly casts.  Suggested by Curro.

Signed-off-by: Ian Romanick <[email protected]>
Reviewed-by: Francisco Jerez <[email protected]>

2 files changed, 26 insertions, 15 deletions

diff --git a/src/glsl/ir.h b/src/glsl/ir.h
index b95ba2c761b..09275b3ccb0 100644
--- a/src/glsl/ir.h
+++ b/src/glsl/ir.h
@@ -196,7 +196,8 @@ public:
     * in particular.  No support for other instruction types (assignments,
     * jumps, calls, etc.) is planned.
     */
-   virtual bool equals(ir_instruction *ir, enum ir_node_type ignore = ir_type_unset);
+   virtual bool equals(const ir_instruction *ir,
+                       enum ir_node_type ignore = ir_type_unset) const;
 
 protected:
    ir_instruction(enum ir_node_type t)
@@ -1611,7 +1612,8 @@ public:
     */
    ir_expression(int op, ir_rvalue *op0, ir_rvalue *op1, ir_rvalue *op2);
 
-   virtual bool equals(ir_instruction *ir, enum ir_node_type ignore = ir_type_unset);
+   virtual bool equals(const ir_instruction *ir,
+                       enum ir_node_type ignore = ir_type_unset) const;
 
    virtual ir_expression *clone(void *mem_ctx, struct hash_table *ht) const;
 
@@ -1922,7 +1924,8 @@ public:
 
    virtual ir_visitor_status accept(ir_hierarchical_visitor *);
 
-   virtual bool equals(ir_instruction *ir, enum ir_node_type ignore = ir_type_unset);
+   virtual bool equals(const ir_instruction *ir,
+                       enum ir_node_type ignore = ir_type_unset) const;
 
    /**
     * Return a string representing the ir_texture_opcode.
@@ -2023,7 +2026,8 @@ public:
 
    virtual ir_visitor_status accept(ir_hierarchical_visitor *);
 
-   virtual bool equals(ir_instruction *ir, enum ir_node_type ignore = ir_type_unset);
+   virtual bool equals(const ir_instruction *ir,
+                       enum ir_node_type ignore = ir_type_unset) const;
 
    bool is_lvalue() const
    {
@@ -2076,7 +2080,8 @@ public:
 
    virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);
 
-   virtual bool equals(ir_instruction *ir, enum ir_node_type ignore = ir_type_unset);
+   virtual bool equals(const ir_instruction *ir,
+                       enum ir_node_type ignore = ir_type_unset) const;
 
    /**
     * Get the variable that is ultimately referenced by an r-value
@@ -2122,7 +2127,8 @@ public:
 
    virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);
 
-   virtual bool equals(ir_instruction *ir, enum ir_node_type ignore = ir_type_unset);
+   virtual bool equals(const ir_instruction *ir,
+                       enum ir_node_type ignore = ir_type_unset) const;
 
    /**
     * Get the variable that is ultimately referenced by an r-value
@@ -2232,7 +2238,8 @@ public:
 
    virtual ir_visitor_status accept(ir_hierarchical_visitor *);
 
-   virtual bool equals(ir_instruction *ir, enum ir_node_type ignore = ir_type_unset);
+   virtual bool equals(const ir_instruction *ir,
+                       enum ir_node_type ignore = ir_type_unset) const;
 
    /**
     * Get a particular component of a constant as a specific type
diff --git a/src/glsl/ir_equals.cpp b/src/glsl/ir_equals.cpp
index 65376cd943b..cc1964eefee 100644
--- a/src/glsl/ir_equals.cpp
+++ b/src/glsl/ir_equals.cpp
@@ -28,7 +28,8 @@
  * can't access a's vtable in that case.
  */
 static bool
-possibly_null_equals(ir_instruction *a, ir_instruction *b, enum ir_node_type ignore)
+possibly_null_equals(const ir_instruction *a, const ir_instruction *b,
+                     enum ir_node_type ignore)
 {
    if (!a || !b)
       return !a && !b;
@@ -41,13 +42,13 @@ possibly_null_equals(ir_instruction *a, ir_instruction *b, enum ir_node_type ign
  * about.
  */
 bool
-ir_instruction::equals(ir_instruction *, enum ir_node_type)
+ir_instruction::equals(const ir_instruction *, enum ir_node_type) const
 {
    return false;
 }
 
 bool
-ir_constant::equals(ir_instruction *ir, enum ir_node_type)
+ir_constant::equals(const ir_instruction *ir, enum ir_node_type) const
 {
    const ir_constant *other = ir->as_constant();
    if (!other)
@@ -65,7 +66,8 @@ ir_constant::equals(ir_instruction *ir, enum ir_node_type)
 }
 
 bool
-ir_dereference_variable::equals(ir_instruction *ir, enum ir_node_type)
+ir_dereference_variable::equals(const ir_instruction *ir,
+                                enum ir_node_type) const
 {
    const ir_dereference_variable *other = ir->as_dereference_variable();
    if (!other)
@@ -75,7 +77,8 @@ ir_dereference_variable::equals(ir_instruction *ir, enum ir_node_type)
 }
 
 bool
-ir_dereference_array::equals(ir_instruction *ir, enum ir_node_type ignore)
+ir_dereference_array::equals(const ir_instruction *ir,
+                             enum ir_node_type ignore) const
 {
    const ir_dereference_array *other = ir->as_dereference_array();
    if (!other)
@@ -94,7 +97,8 @@ ir_dereference_array::equals(ir_instruction *ir, enum ir_node_type ignore)
 }
 
 bool
-ir_swizzle::equals(ir_instruction *ir, enum ir_node_type ignore)
+ir_swizzle::equals(const ir_instruction *ir,
+                   enum ir_node_type ignore) const
 {
    const ir_swizzle *other = ir->as_swizzle();
    if (!other)
@@ -116,7 +120,7 @@ ir_swizzle::equals(ir_instruction *ir, enum ir_node_type ignore)
 }
 
 bool
-ir_texture::equals(ir_instruction *ir, enum ir_node_type ignore)
+ir_texture::equals(const ir_instruction *ir, enum ir_node_type ignore) const
 {
    const ir_texture *other = ir->as_texture();
    if (!other)
@@ -179,7 +183,7 @@ ir_texture::equals(ir_instruction *ir, enum ir_node_type ignore)
 }
 
 bool
-ir_expression::equals(ir_instruction *ir, enum ir_node_type ignore)
+ir_expression::equals(const ir_instruction *ir, enum ir_node_type ignore) const
 {
    const ir_expression *other = ir->as_expression();
    if (!other)