From e4e52b06a9dec7d076ceeb4469bb2ca8b37c6cd5 Mon Sep 17 00:00:00 2001

From: Lyude <lyude@redhat.com>

Date: Tue, 2 May 2017 17:05:50 -0400

Subject: [PATCH] Revert "draw: use SoA fetch, not AoS one"

This reverts commit e827d9175675aaa6cfc0b981e2a80685fb7b3a74.

Signed-off-by: Lyude <lyude@redhat.com>

---

 src/gallium/auxiliary/draw/draw_llvm.c | 71 +++++++++++++++++++++++-----------

 1 file changed, 48 insertions(+), 23 deletions(-)

diff --git a/src/gallium/auxiliary/draw/draw_llvm.c b/src/gallium/auxiliary/draw/draw_llvm.c

index 8952dc8..19b75a5 100644

--- a/src/gallium/auxiliary/draw/draw_llvm.c

+++ b/src/gallium/auxiliary/draw/draw_llvm.c

@@ -713,6 +713,39 @@ fetch_instanced(struct gallivm_state *gallivm,

 static void

+convert_to_soa(struct gallivm_state *gallivm,

+               LLVMValueRef src_aos[LP_MAX_VECTOR_WIDTH / 32],

+               LLVMValueRef dst_soa[TGSI_NUM_CHANNELS],

+               const struct lp_type soa_type)

+{

+   unsigned j, k;

+   struct lp_type aos_channel_type = soa_type;

+

+   LLVMValueRef aos_channels[TGSI_NUM_CHANNELS];

+   unsigned pixels_per_channel = soa_type.length / TGSI_NUM_CHANNELS;

+

+   debug_assert(TGSI_NUM_CHANNELS == 4);

+   debug_assert((soa_type.length % TGSI_NUM_CHANNELS) == 0);

+

+   aos_channel_type.length >>= 1;

+

+   for (j = 0; j < TGSI_NUM_CHANNELS; ++j) {

+      LLVMValueRef channel[LP_MAX_VECTOR_LENGTH] = { 0 };

+

+      assert(pixels_per_channel <= LP_MAX_VECTOR_LENGTH);

+

+      for (k = 0; k < pixels_per_channel; ++k) {

+         channel[k] = src_aos[j + TGSI_NUM_CHANNELS * k];

+      }

+

+      aos_channels[j] = lp_build_concat(gallivm, channel, aos_channel_type, pixels_per_channel);

+   }

+

+   lp_build_transpose_aos(gallivm, soa_type, aos_channels, dst_soa);

+}

+

+

+static void

 fetch_vector(struct gallivm_state *gallivm,

              const struct util_format_description *format_desc,

              struct lp_type vs_type,

@@ -722,10 +755,11 @@ fetch_vector(struct gallivm_state *gallivm,

              LLVMValueRef *inputs,

              LLVMValueRef indices)

 {

+   LLVMValueRef zero = LLVMConstNull(LLVMInt32TypeInContext(gallivm->context));

    LLVMBuilderRef builder = gallivm->builder;

    struct lp_build_context blduivec;

-   struct lp_type fetch_type = vs_type;

    LLVMValueRef offset, valid_mask;

+   LLVMValueRef aos_fetch[LP_MAX_VECTOR_WIDTH / 32];

    unsigned i;

    lp_build_context_init(&blduivec, gallivm, lp_uint_type(vs_type));

@@ -749,37 +783,28 @@ fetch_vector(struct gallivm_state *gallivm,

    }

    /*

-    * Unlike fetch_instanced, use SoA fetch instead of multiple AoS fetches.

-    * This should always produce better code.

+    * Note: we probably really want to use SoA fetch, not AoS one (albeit

+    * for most formats it will amount to the same as this isn't very

+    * optimized). But looks dangerous since it assumes alignment.

     */

+   for (i = 0; i < vs_type.length; i++) {

+      LLVMValueRef offset1, elem;

+      elem = lp_build_const_int32(gallivm, i);

+      offset1 = LLVMBuildExtractElement(builder, offset, elem, "");

-   /* The type handling is annoying here... */

-   if (format_desc->colorspace == UTIL_FORMAT_COLORSPACE_RGB &&

-       format_desc->channel[0].pure_integer) {

-      if (format_desc->channel[0].type == UTIL_FORMAT_TYPE_SIGNED) {

-         fetch_type = lp_type_int_vec(vs_type.width, vs_type.width * vs_type.length);

-      }

-      else if (format_desc->channel[0].type == UTIL_FORMAT_TYPE_UNSIGNED) {

-         fetch_type = lp_type_uint_vec(vs_type.width, vs_type.width * vs_type.length);

-      }

-   }

-

-   lp_build_fetch_rgba_soa(gallivm, format_desc,

-                           fetch_type, FALSE, map_ptr, offset,

-                           blduivec.zero, blduivec.zero,

-                           NULL, inputs);

-

-   for (i = 0; i < TGSI_NUM_CHANNELS; i++) {

-      inputs[i] = LLVMBuildBitCast(builder, inputs[i],

-                                   lp_build_vec_type(gallivm, vs_type), "");

+      aos_fetch[i] = lp_build_fetch_rgba_aos(gallivm, format_desc,

+                                             lp_float32_vec4_type(),

+                                             FALSE, map_ptr, offset1,

+                                             zero, zero, NULL);

    }

+   convert_to_soa(gallivm, aos_fetch, inputs, vs_type);

-   /* out-of-bound fetches return all zeros */

    for (i = 0; i < TGSI_NUM_CHANNELS; i++) {

       inputs[i] = LLVMBuildBitCast(builder, inputs[i], blduivec.vec_type, "");

       inputs[i] = LLVMBuildAnd(builder, inputs[i], valid_mask, "");

       inputs[i] = LLVMBuildBitCast(builder, inputs[i],

                                    lp_build_vec_type(gallivm, vs_type), "");

+

    }

 }

-- 

2.9.3