nir: Add alignment parameters to SSBO, UBO, and shared access

This also changes spirv_to_nir and glsl_to_nir to set them.  The one
place that doesn't set them is shared memory access lowering in
nir_lower_io.  That will have to be updated before any consumers of it
can effectively use these new alignments.

Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Acked-by: Karol Herbst <kherbst@redhat.com>

7 files changed, 85 insertions, 10 deletions

diff --git a/src/compiler/glsl/glsl_to_nir.cpp b/src/compiler/glsl/glsl_to_nir.cpp
index 9bb0f5d4044..9f73b721e39 100644
--- a/src/compiler/glsl/glsl_to_nir.cpp
+++ b/src/compiler/glsl/glsl_to_nir.cpp
@@ -33,6 +33,7 @@
 #include "compiler/nir/nir_builder.h"
 #include "main/imports.h"
 #include "main/mtypes.h"
+#include "util/u_math.h"
 
 /*
  * pass to lower GLSL IR to NIR
@@ -603,6 +604,14 @@ nir_visitor::visit(ir_return *ir)
    nir_builder_instr_insert(&b, &instr->instr);
 }
 
+static void
+intrinsic_set_std430_align(nir_intrinsic_instr *intrin, const glsl_type *type)
+{
+   unsigned bit_size = type->is_boolean() ? 32 : glsl_get_bit_size(type);
+   unsigned pow2_components = util_next_power_of_two(type->vector_elements);
+   nir_intrinsic_set_align(intrin, (bit_size / 8) * pow2_components, 0);
+}
+
 void
 nir_visitor::visit(ir_call *ir)
 {
@@ -1006,6 +1015,7 @@ nir_visitor::visit(ir_call *ir)
          instr->src[0] = nir_src_for_ssa(nir_val);
          instr->src[1] = nir_src_for_ssa(evaluate_rvalue(block));
          instr->src[2] = nir_src_for_ssa(evaluate_rvalue(offset));
+         intrinsic_set_std430_align(instr, val->type);
          nir_intrinsic_set_write_mask(instr, write_mask->value.u[0]);
          instr->num_components = val->type->vector_elements;
 
@@ -1024,6 +1034,7 @@ nir_visitor::visit(ir_call *ir)
 
          const glsl_type *type = ir->return_deref->var->type;
          instr->num_components = type->vector_elements;
+         intrinsic_set_std430_align(instr, type);
 
          /* Setup destination register */
          unsigned bit_size = type->is_boolean() ? 32 : glsl_get_bit_size(type);
@@ -1101,6 +1112,7 @@ nir_visitor::visit(ir_call *ir)
 
          const glsl_type *type = ir->return_deref->var->type;
          instr->num_components = type->vector_elements;
+         intrinsic_set_std430_align(instr, type);
 
          /* Setup destination register */
          unsigned bit_size = type->is_boolean() ? 32 : glsl_get_bit_size(type);
@@ -1131,6 +1143,7 @@ nir_visitor::visit(ir_call *ir)
 
          instr->src[0] = nir_src_for_ssa(nir_val);
          instr->num_components = val->type->vector_elements;
+         intrinsic_set_std430_align(instr, val->type);
 
          nir_builder_instr_insert(&b, &instr->instr);
          break;
@@ -1388,6 +1401,7 @@ nir_visitor::visit(ir_expression *ir)
       load->num_components = ir->type->vector_elements;
       load->src[0] = nir_src_for_ssa(evaluate_rvalue(ir->operands[0]));
       load->src[1] = nir_src_for_ssa(evaluate_rvalue(ir->operands[1]));
+      intrinsic_set_std430_align(load, ir->type);
       add_instr(&load->instr, ir->type->vector_elements, bit_size);
 
       /*
diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
index e542e08759d..b0cff50eaf2 100644
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -34,6 +34,7 @@
 #include "util/list.h"
 #include "util/ralloc.h"
 #include "util/set.h"
+#include "util/bitscan.h"
 #include "util/bitset.h"
 #include "util/macros.h"
 #include "compiler/nir_types.h"
@@ -1248,6 +1249,18 @@ typedef enum {
     */
    NIR_INTRINSIC_ACCESS = 16,
 
+   /**
+    * Alignment for offsets and addresses
+    *
+    * These two parameters, specify an alignment in terms of a multiplier and
+    * an offset.  The offset or address parameter X of the intrinsic is
+    * guaranteed to satisfy the following:
+    *
+    *                (X - align_offset) % align_mul == 0
+    */
+   NIR_INTRINSIC_ALIGN_MUL = 17,
+   NIR_INTRINSIC_ALIGN_OFFSET = 18,
+
    NIR_INTRINSIC_NUM_INDEX_FLAGS,
 
 } nir_intrinsic_index_flag;
@@ -1342,6 +1355,34 @@ INTRINSIC_IDX_ACCESSORS(image_dim, IMAGE_DIM, enum glsl_sampler_dim)
 INTRINSIC_IDX_ACCESSORS(image_array, IMAGE_ARRAY, bool)
 INTRINSIC_IDX_ACCESSORS(access, ACCESS, enum gl_access_qualifier)
 INTRINSIC_IDX_ACCESSORS(format, FORMAT, unsigned)
+INTRINSIC_IDX_ACCESSORS(align_mul, ALIGN_MUL, unsigned)
+INTRINSIC_IDX_ACCESSORS(align_offset, ALIGN_OFFSET, unsigned)
+
+static inline void
+nir_intrinsic_set_align(nir_intrinsic_instr *intrin,
+                        unsigned align_mul, unsigned align_offset)
+{
+   assert(util_is_power_of_two_nonzero(align_mul));
+   assert(align_offset < align_mul);
+   nir_intrinsic_set_align_mul(intrin, align_mul);
+   nir_intrinsic_set_align_offset(intrin, align_offset);
+}
+
+/** Returns a simple alignment for a load/store intrinsic offset
+ *
+ * Instead of the full mul+offset alignment scheme provided by the ALIGN_MUL
+ * and ALIGN_OFFSET parameters, this helper takes both into account and
+ * provides a single simple alignment parameter.  The offset X is guaranteed
+ * to satisfy X % align == 0.
+ */
+static inline unsigned
+nir_intrinsic_align(nir_intrinsic_instr *intrin)
+{
+   const unsigned align_mul = nir_intrinsic_align_mul(intrin);
+   const unsigned align_offset = nir_intrinsic_align_offset(intrin);
+   assert(align_offset < align_mul);
+   return align_offset ? 1 << (ffs(align_offset) - 1) : align_mul;
+}
 
 /**
  * \group texture information
diff --git a/src/compiler/nir/nir_intrinsics.py b/src/compiler/nir/nir_intrinsics.py
index ec3049ca06d..735db43d16a 100644
--- a/src/compiler/nir/nir_intrinsics.py
+++ b/src/compiler/nir/nir_intrinsics.py
@@ -109,6 +109,9 @@ IMAGE_ARRAY = "NIR_INTRINSIC_IMAGE_ARRAY"
 ACCESS = "NIR_INTRINSIC_ACCESS"
 # Image format for image intrinsics
 FORMAT = "NIR_INTRINSIC_FORMAT"
+# Offset or address alignment
+ALIGN_MUL = "NIR_INTRINSIC_ALIGN_MUL"
+ALIGN_OFFSET = "NIR_INTRINSIC_ALIGN_OFFSET"
 
 #
 # Possible flags:
@@ -554,8 +557,8 @@ def load(name, num_srcs, indices=[], flags=[]):
 
 # src[] = { offset }. const_index[] = { base, range }
 load("uniform", 1, [BASE, RANGE], [CAN_ELIMINATE, CAN_REORDER])
-# src[] = { buffer_index, offset }. No const_index
-load("ubo", 2, flags=[CAN_ELIMINATE, CAN_REORDER])
+# src[] = { buffer_index, offset }. const_index[] = { align_mul, align_offset }
+load("ubo", 2, [ALIGN_MUL, ALIGN_OFFSET], flags=[CAN_ELIMINATE, CAN_REORDER])
 # src[] = { offset }. const_index[] = { base, component }
 load("input", 1, [BASE, COMPONENT], [CAN_ELIMINATE, CAN_REORDER])
 # src[] = { vertex, offset }. const_index[] = { base, component }
@@ -564,14 +567,15 @@ load("per_vertex_input", 2, [BASE, COMPONENT], [CAN_ELIMINATE, CAN_REORDER])
 intrinsic("load_interpolated_input", src_comp=[2, 1], dest_comp=0,
           indices=[BASE, COMPONENT], flags=[CAN_ELIMINATE, CAN_REORDER])
 
-# src[] = { buffer_index, offset }. No const_index
-load("ssbo", 2, flags=[CAN_ELIMINATE], indices=[ACCESS])
+# src[] = { buffer_index, offset }.
+# const_index[] = { access, align_mul, align_offset }
+load("ssbo", 2, [ACCESS, ALIGN_MUL, ALIGN_OFFSET], [CAN_ELIMINATE])
 # src[] = { offset }. const_index[] = { base, component }
 load("output", 1, [BASE, COMPONENT], flags=[CAN_ELIMINATE])
 # src[] = { vertex, offset }. const_index[] = { base }
 load("per_vertex_output", 2, [BASE, COMPONENT], [CAN_ELIMINATE])
-# src[] = { offset }. const_index[] = { base }
-load("shared", 1, [BASE], [CAN_ELIMINATE])
+# src[] = { offset }. const_index[] = { base, align_mul, align_offset }
+load("shared", 1, [BASE, ALIGN_MUL, ALIGN_OFFSET], [CAN_ELIMINATE])
 # src[] = { offset }. const_index[] = { base, range }
 load("push_constant", 1, [BASE, RANGE], [CAN_ELIMINATE, CAN_REORDER])
 # src[] = { offset }. const_index[] = { base, range }
@@ -590,7 +594,9 @@ store("output", 2, [BASE, WRMASK, COMPONENT])
 # src[] = { value, vertex, offset }.
 # const_index[] = { base, write_mask, component }
 store("per_vertex_output", 3, [BASE, WRMASK, COMPONENT])
-# src[] = { value, block_index, offset }. const_index[] = { write_mask }
-store("ssbo", 3, [WRMASK, ACCESS])
-# src[] = { value, offset }. const_index[] = { base, write_mask }
-store("shared", 2, [BASE, WRMASK])
+# src[] = { value, block_index, offset }
+# const_index[] = { write_mask, access, align_mul, align_offset }
+store("ssbo", 3, [WRMASK, ACCESS, ALIGN_MUL, ALIGN_OFFSET])
+# src[] = { value, offset }.
+# const_index[] = { base, write_mask, align_mul, align_offset }
+store("shared", 2, [BASE, WRMASK, ALIGN_MUL, ALIGN_OFFSET])
diff --git a/src/compiler/nir/nir_lower_atomics_to_ssbo.c b/src/compiler/nir/nir_lower_atomics_to_ssbo.c
index c165a03b141..cdc660981fc 100644
--- a/src/compiler/nir/nir_lower_atomics_to_ssbo.c
+++ b/src/compiler/nir/nir_lower_atomics_to_ssbo.c
@@ -149,6 +149,10 @@ lower_instr(nir_intrinsic_instr *instr, unsigned ssbo_offset, nir_builder *b)
       break;
    }
 
+   if (new_instr->intrinsic == nir_intrinsic_load_ssbo ||
+       new_instr->intrinsic == nir_intrinsic_store_ssbo)
+      nir_intrinsic_set_align(new_instr, 4, 0);
+
    nir_ssa_dest_init(&new_instr->instr, &new_instr->dest,
                      instr->dest.ssa.num_components,
                      instr->dest.ssa.bit_size, NULL);
diff --git a/src/compiler/nir/nir_print.c b/src/compiler/nir/nir_print.c
index ab3d5115688..e20c28fec87 100644
--- a/src/compiler/nir/nir_print.c
+++ b/src/compiler/nir/nir_print.c
@@ -691,6 +691,8 @@ print_intrinsic_instr(nir_intrinsic_instr *instr, print_state *state)
       [NIR_INTRINSIC_IMAGE_ARRAY] = "image_array",
       [NIR_INTRINSIC_ACCESS] = "access",
       [NIR_INTRINSIC_FORMAT] = "format",
+      [NIR_INTRINSIC_ALIGN_MUL] = "align_mul",
+      [NIR_INTRINSIC_ALIGN_OFFSET] = "align_offset",
    };
    for (unsigned idx = 1; idx < NIR_INTRINSIC_NUM_INDEX_FLAGS; idx++) {
       if (!info->index_map[idx])
diff --git a/src/compiler/spirv/spirv_to_nir.c b/src/compiler/spirv/spirv_to_nir.c
index 77ce0be369e..4fa02b6fd7b 100644
--- a/src/compiler/spirv/spirv_to_nir.c
+++ b/src/compiler/spirv/spirv_to_nir.c
@@ -2762,6 +2762,7 @@ vtn_handle_atomics(struct vtn_builder *b, SpvOp opcode,
       switch (opcode) {
       case SpvOpAtomicLoad:
          atomic->num_components = glsl_get_vector_elements(ptr->type->type);
+         nir_intrinsic_set_align(atomic, 4, 0);
          if (ptr->mode == vtn_variable_mode_ssbo)
             atomic->src[src++] = nir_src_for_ssa(index);
          atomic->src[src++] = nir_src_for_ssa(offset);
@@ -2770,6 +2771,7 @@ vtn_handle_atomics(struct vtn_builder *b, SpvOp opcode,
       case SpvOpAtomicStore:
          atomic->num_components = glsl_get_vector_elements(ptr->type->type);
          nir_intrinsic_set_write_mask(atomic, (1 << atomic->num_components) - 1);
+         nir_intrinsic_set_align(atomic, 4, 0);
          atomic->src[src++] = nir_src_for_ssa(vtn_ssa_value(b, w[4])->def);
          if (ptr->mode == vtn_variable_mode_ssbo)
             atomic->src[src++] = nir_src_for_ssa(index);
diff --git a/src/compiler/spirv/vtn_variables.c b/src/compiler/spirv/vtn_variables.c
index e1e2c8c26ba..53f52255dc3 100644
--- a/src/compiler/spirv/vtn_variables.c
+++ b/src/compiler/spirv/vtn_variables.c
@@ -646,6 +646,12 @@ _vtn_load_store_tail(struct vtn_builder *b, nir_intrinsic_op op, bool load,
       nir_intrinsic_set_access(instr, access);
    }
 
+   /* With extensions like relaxed_block_layout, we really can't guarantee
+    * much more than scalar alignment.
+    */
+   if (op != nir_intrinsic_load_push_constant)
+      nir_intrinsic_set_align(instr, data_bit_size / 8, 0);
+
    if (index)
       instr->src[src++] = nir_src_for_ssa(index);