nir: Add an ALU op builder kind of like ir_builder.h

v2: Rebase on the nir_opcodes.h python code generation support.
v3: Use SSA values, and set an appropriate writemask on dot products.
v4: Make the arguments be SSA references as well.  This lets you stack up
    expressions in the arguments of other expressions, at the cost of
    having to insert a fmov/imov if you want to swizzle.  Also, add
    the generated file to NIR_GENERATED_FILES.
v5: Use more pythonish style for iterating the list.
v6: Infer the size of the dest from the size of the srcs, and auto-swizzle
    a single small src out to the appropriate size.
v7: Add little helpers for initializing the struct, add a typedef for the
    struct like other nir types have.

Reviewed-by: Kenneth Graunke <[email protected]> (v6)
Reviewed-by: Connor Abbott <[email protected]> (v7)

1 files changed, 130 insertions, 0 deletions

diff --git a/src/glsl/nir/nir_builder.h b/src/glsl/nir/nir_builder.h
new file mode 100644
index 00000000000..7c4f7fd96cd
--- /dev/null
+++ b/src/glsl/nir/nir_builder.h
@@ -0,0 +1,130 @@
+/*
+ * Copyright © 2014-2015 Broadcom
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef NIR_BUILDER_H
+#define NIR_BUILDER_H
+
+struct exec_list;
+
+typedef struct nir_builder {
+   struct exec_list *cf_node_list;
+   nir_shader *shader;
+   nir_function_impl *impl;
+} nir_builder;
+
+static inline void
+nir_builder_init(nir_builder *build, nir_function_impl *impl)
+{
+   memset(build, 0, sizeof(*build));
+   build->impl = impl;
+   build->shader = impl->overload->function->shader;
+}
+
+static inline void
+nir_builder_insert_after_cf_list(nir_builder *build,
+                                 struct exec_list *cf_node_list)
+{
+   build->cf_node_list = cf_node_list;
+}
+
+
+static inline nir_ssa_def *
+nir_build_alu(nir_builder *build, nir_op op, nir_ssa_def *src0,
+              nir_ssa_def *src1, nir_ssa_def *src2, nir_ssa_def *src3)
+{
+   const nir_op_info *op_info = &nir_op_infos[op];
+   nir_alu_instr *instr = nir_alu_instr_create(build->shader, op);
+   if (!instr)
+      return NULL;
+
+   instr->src[0].src = nir_src_for_ssa(src0);
+   if (src1)
+      instr->src[1].src = nir_src_for_ssa(src1);
+   if (src2)
+      instr->src[2].src = nir_src_for_ssa(src2);
+   if (src3)
+      instr->src[3].src = nir_src_for_ssa(src3);
+
+   /* Guess the number of components the destination temporary should have
+    * based on our input sizes, if it's not fixed for the op.
+    */
+   unsigned num_components = op_info->output_size;
+   if (num_components == 0) {
+      for (unsigned i = 0; i < op_info->num_inputs; i++) {
+         if (op_info->input_sizes[i] == 0)
+            num_components = MAX2(num_components,
+                                  instr->src[i].src.ssa->num_components);
+      }
+   }
+   assert(num_components != 0);
+
+   /* Make sure we don't swizzle from outside of our source vector (like if a
+    * scalar value was passed into a multiply with a vector).
+    */
+   for (unsigned i = 0; i < op_info->num_inputs; i++) {
+      for (unsigned j = instr->src[i].src.ssa->num_components; j < 4; j++) {
+         instr->src[i].swizzle[j] = instr->src[i].src.ssa->num_components - 1;
+      }
+   }
+
+   nir_ssa_dest_init(&instr->instr, &instr->dest.dest, num_components, NULL);
+   instr->dest.write_mask = (1 << num_components) - 1;
+
+   nir_instr_insert_after_cf_list(build->cf_node_list, &instr->instr);
+
+   return &instr->dest.dest.ssa;
+}
+
+#define ALU1(op)                                                          \
+static inline nir_ssa_def *                                               \
+nir_##op(nir_builder *build, nir_ssa_def *src0)                           \
+{                                                                         \
+   return nir_build_alu(build, nir_op_##op, src0, NULL, NULL, NULL);      \
+}
+
+#define ALU2(op)                                                          \
+static inline nir_ssa_def *                                               \
+nir_##op(nir_builder *build, nir_ssa_def *src0, nir_ssa_def *src1)        \
+{                                                                         \
+   return nir_build_alu(build, nir_op_##op, src0, src1, NULL, NULL);      \
+}
+
+#define ALU3(op)                                                          \
+static inline nir_ssa_def *                                               \
+nir_##op(nir_builder *build, nir_ssa_def *src0,                           \
+         nir_ssa_def *src1, nir_ssa_def *src2)                            \
+{                                                                         \
+   return nir_build_alu(build, nir_op_##op, src0, src1, src2, NULL);      \
+}
+
+#define ALU4(op)                                                          \
+static inline nir_ssa_def *                                               \
+nir_##op(nir_builder *build, nir_ssa_def *src0,                           \
+         nir_ssa_def *src1, nir_ssa_def *src2, nir_ssa_def *src3)         \
+{                                                                         \
+   return nir_build_alu(build, nir_op_##op, src0, src1, src2, src3);      \
+}
+
+#include "nir_builder_opcodes.h"
+
+#endif /* NIR_BUILDER_H */