From f534c2c539f1a4722c03c63a257e99b052e6f1a8 Mon Sep 17 00:00:00 2001
From: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Date: Fri, 26 May 2023 11:10:58 -0400
Subject: [PATCH] nir/builder: Add nir_replicate helper

Splat a scalar to all components of a vector.

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Acked-by: Jesse Natalie <jenatali@microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23259>
---
 src/compiler/nir/nir_builder.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/compiler/nir/nir_builder.h b/src/compiler/nir/nir_builder.h
index c6a476fa6b8..c1d676896ba 100644
--- a/src/compiler/nir/nir_builder.h
+++ b/src/compiler/nir/nir_builder.h
@@ -707,6 +707,19 @@ nir_vector_insert(nir_builder *b, nir_ssa_def *vec, nir_ssa_def *scalar,
    }
 }
 
+static inline nir_ssa_def *
+nir_replicate(nir_builder *b, nir_ssa_def *scalar, unsigned num_components)
+{
+   assert(scalar->num_components == 1);
+   assert(num_components < NIR_MAX_VEC_COMPONENTS);
+
+   nir_ssa_def *copies[NIR_MAX_VEC_COMPONENTS] = {NULL};
+   for (unsigned i = 0; i < num_components; ++i)
+      copies[i] = scalar;
+
+   return nir_vec(b, copies, num_components);
+}
+
 static inline nir_ssa_def *
 nir_iadd_imm(nir_builder *build, nir_ssa_def *x, uint64_t y)
 {