Add Spec Constant API (#242)

Author: spencer-lunarg

common/output_stream.cpp

@@ -2172,6 +2172,15 @@ void SpvReflectToYaml::Write(std::ostream& os) {
     os << t2 << "- *bv" << itor->second << " # " << SafeString(sm_.push_constant_blocks[i].name) << std::endl;
   }
 
+  // uint32_t                            spec_constant_count;
+  os << t1 << "specialization_constant_count: " << sm_.spec_constant_count << ",\n";
+  // SpvReflectSpecializationConstant*   spec_constants;
+  os << t1 << "specialization_constants:" << std::endl;
+  for (uint32_t i = 0; i < sm_.spec_constant_count; ++i) {
+    os << t3 << "spirv_id: " << sm_.spec_constants[i].spirv_id << std::endl;
+    os << t3 << "constant_id: " << sm_.spec_constants[i].constant_id << std::endl;
+  }
+
   if (verbosity_ >= 2) {
     // struct Internal {
     os << t1 << "_internal:" << std::endl;

spirv_reflect.c

@@ -1352,7 +1352,8 @@ static SpvReflectResult ParseNames(SpvReflectPrvParser* p_parser) {
   return SPV_REFLECT_RESULT_SUCCESS;
 }
 
-static SpvReflectResult ParseDecorations(SpvReflectPrvParser* p_parser) {
+static SpvReflectResult ParseDecorations(SpvReflectPrvParser* p_parser, SpvReflectShaderModule* p_module) {
+  uint32_t spec_constant_count = 0;
   for (uint32_t i = 0; i < p_parser->node_count; ++i) {
     SpvReflectPrvNode* p_node = &(p_parser->nodes[i]);
 
@@ -1538,8 +1539,7 @@ static SpvReflectResult ParseDecorations(SpvReflectPrvParser* p_parser) {
       } break;
 
       case SpvDecorationSpecId: {
-        uint32_t word_offset = p_node->word_offset + member_offset + 3;
-        CHECKED_READU32(p_parser, word_offset, p_target_decorations->spec_id);
+        spec_constant_count++;
       } break;
 
       case SpvDecorationHlslCounterBufferGOOGLE: {
@@ -1563,6 +1563,27 @@ static SpvReflectResult ParseDecorations(SpvReflectPrvParser* p_parser) {
       } break;
     }
   }
+
+  if (spec_constant_count > 0) {
+    p_module->spec_constants = (SpvReflectSpecializationConstant*)calloc(spec_constant_count, sizeof(*p_module->spec_constants));
+    if (IsNull(p_module->spec_constants)) {
+      return SPV_REFLECT_RESULT_ERROR_ALLOC_FAILED;
+    }
+  }
+  for (uint32_t i = 0; i < p_parser->node_count; ++i) {
+    SpvReflectPrvNode* p_node = &(p_parser->nodes[i]);
+    if (p_node->op == SpvOpDecorate) {
+      uint32_t decoration = (uint32_t)INVALID_VALUE;
+      CHECKED_READU32(p_parser, p_node->word_offset + 2, decoration);
+      if (decoration == SpvDecorationSpecId) {
+        const uint32_t count = p_module->spec_constant_count;
+        CHECKED_READU32(p_parser, p_node->word_offset + 1, p_module->spec_constants[count].constant_id);
+        CHECKED_READU32(p_parser, p_node->word_offset + 3, p_module->spec_constants[count].spirv_id);
+        p_module->spec_constant_count++;
+      }
+    }
+  }
+
   return SPV_REFLECT_RESULT_SUCCESS;
 }
 
@@ -3861,7 +3882,7 @@ static SpvReflectResult CreateShaderModule(uint32_t flags, size_t size, const vo
     SPV_REFLECT_ASSERT(result == SPV_REFLECT_RESULT_SUCCESS);
   }
   if (result == SPV_REFLECT_RESULT_SUCCESS) {
-    result = ParseDecorations(&parser);
+    result = ParseDecorations(&parser, p_module);
     SPV_REFLECT_ASSERT(result == SPV_REFLECT_RESULT_SUCCESS);
   }
 
@@ -4050,6 +4071,7 @@ void spvReflectDestroyShaderModule(SpvReflectShaderModule* p_module) {
   }
   SafeFree(p_module->capabilities);
   SafeFree(p_module->entry_points);
+  SafeFree(p_module->spec_constants);
 
   // Push constants
   for (size_t i = 0; i < p_module->push_constant_block_count; ++i) {
@@ -4455,6 +4477,31 @@ SpvReflectResult spvReflectEnumerateEntryPointPushConstantBlocks(const SpvReflec
   return SPV_REFLECT_RESULT_SUCCESS;
 }
 
+SpvReflectResult spvReflectEnumerateSpecializationConstants(const SpvReflectShaderModule* p_module, uint32_t* p_count,
+                                                            SpvReflectSpecializationConstant** pp_constants) {
+  if (IsNull(p_module)) {
+    return SPV_REFLECT_RESULT_ERROR_NULL_POINTER;
+  }
+  if (IsNull(p_count)) {
+    return SPV_REFLECT_RESULT_ERROR_NULL_POINTER;
+  }
+
+  if (IsNotNull(pp_constants)) {
+    if (*p_count != p_module->spec_constant_count) {
+      return SPV_REFLECT_RESULT_ERROR_COUNT_MISMATCH;
+    }
+
+    for (uint32_t index = 0; index < *p_count; ++index) {
+      SpvReflectSpecializationConstant* p_constant = (SpvReflectSpecializationConstant*)&p_module->spec_constants[index];
+      pp_constants[index] = p_constant;
+    }
+  } else {
+    *p_count = p_module->spec_constant_count;
+  }
+
+  return SPV_REFLECT_RESULT_SUCCESS;
+}
+
 const SpvReflectDescriptorBinding* spvReflectGetDescriptorBinding(const SpvReflectShaderModule* p_module, uint32_t binding_number,
                                                                   uint32_t set_number, SpvReflectResult* p_result) {
   const SpvReflectDescriptorBinding* p_descriptor = NULL;

spirv_reflect.h

@@ -519,6 +519,15 @@ typedef struct SpvReflectCapability {
   uint32_t                          word_offset;
 } SpvReflectCapability;
 
+
+/*! @struct SpvReflectSpecId
+
+*/
+typedef struct SpvReflectSpecializationConstant {
+  uint32_t spirv_id;
+  uint32_t constant_id;
+} SpvReflectSpecializationConstant;
+
 /*! @struct SpvReflectShaderModule
 
 */
@@ -548,6 +557,8 @@ typedef struct SpvReflectShaderModule {
   SpvReflectInterfaceVariable*      interface_variables;                              // Uses value(s) from first entry point
   uint32_t                          push_constant_block_count;                        // Uses value(s) from first entry point
   SpvReflectBlockVariable*          push_constant_blocks;                             // Uses value(s) from first entry point
+  uint32_t                          spec_constant_count;                              // Uses value(s) from first entry point
+  SpvReflectSpecializationConstant* spec_constants;                                   // Uses value(s) from first entry point
 
   struct Internal {
     SpvReflectModuleFlags           module_flags;
@@ -959,6 +970,25 @@ SpvReflectResult spvReflectEnumerateEntryPointPushConstantBlocks(
 );
 
 
+/*! @fn spvReflectEnumerateSpecializationConstants
+ @param  p_module      Pointer to an instance of SpvReflectShaderModule.
+ @param  p_count       If pp_blocks is NULL, the module's specialization constant
+                       count will be stored here. If pp_blocks is not NULL, *p_count
+                       must contain the module's specialization constant count.
+ @param  pp_constants  If NULL, the module's specialization constant count
+                       will be written to *p_count. If non-NULL, pp_blocks must
+                       point to an array with *p_count entries, where pointers to
+                       the module's specialization constant blocks will be written.
+                       The caller must not free the  variables written to this array.
+ @return               If successful, returns SPV_REFLECT_RESULT_SUCCESS.
+                       Otherwise, the error code indicates the cause of the failure.
+*/
+SpvReflectResult spvReflectEnumerateSpecializationConstants(
+  const SpvReflectShaderModule*      p_module,
+  uint32_t*                          p_count,
+  SpvReflectSpecializationConstant** pp_constants
+);
+
 /*! @fn spvReflectGetDescriptorBinding
 
  @param  p_module        Pointer to an instance of SpvReflectShaderModule.
@@ -1549,6 +1579,7 @@ class ShaderModule {
   SpvReflectResult  EnumeratePushConstants(uint32_t* p_count, SpvReflectBlockVariable** pp_blocks) const {
     return EnumeratePushConstantBlocks(p_count, pp_blocks);
   }
+  SpvReflectResult  EnumerateSpecializationConstants(uint32_t* p_count, SpvReflectSpecializationConstant** pp_constants) const;
 
   const SpvReflectDescriptorBinding*  GetDescriptorBinding(uint32_t binding_number, uint32_t set_number, SpvReflectResult* p_result = nullptr) const;
   const SpvReflectDescriptorBinding*  GetEntryPointDescriptorBinding(const char* entry_point, uint32_t binding_number, uint32_t set_number, SpvReflectResult* p_result = nullptr) const;
@@ -1996,6 +2027,24 @@ inline SpvReflectResult ShaderModule::EnumeratePushConstantBlocks(
   return m_result;
 }
 
+/*! @fn EnumerateSpecializationConstants
+  @param  p_count
+  @param  pp_constants
+  @return
+*/
+inline SpvReflectResult ShaderModule::EnumerateSpecializationConstants(
+    uint32_t*                          p_count,
+    SpvReflectSpecializationConstant** pp_constants
+) const
+{
+  m_result = spvReflectEnumerateSpecializationConstants(
+    &m_module,
+    p_count,
+    pp_constants
+  );
+  return m_result;
+}
+
 /*! @fn EnumerateEntryPointPushConstantBlocks
 
   @param  entry_point

tests/16bit/vert_in_out_16.spv.yaml

@@ -352,4 +352,6 @@ module:
     - *iv11 # "_f"
   push_constant_count: 0,
   push_constants:
+  specialization_constant_count: 0,
+  specialization_constants:
 ...

tests/access_chains/array_length_from_access_chain.spv.yaml

@@ -143,4 +143,6 @@ module:
   output_variables:
   push_constant_count: 0,
   push_constants:
+  specialization_constant_count: 0,
+  specialization_constants:
 ...

tests/cbuffer_unused/cbuffer_unused_001.spv.yaml

@@ -3393,4 +3393,6 @@ module:
     - *iv1 # 
   push_constant_count: 0,
   push_constants:
+  specialization_constant_count: 0,
+  specialization_constants:
 ...

tests/entry_exec_mode/comp_local_size.spv.yaml

@@ -109,4 +109,6 @@ module:
   output_variables:
   push_constant_count: 0,
   push_constants:
+  specialization_constant_count: 0,
+  specialization_constants:
 ...

tests/entry_exec_mode/geom_inv_out_vert.spv.yaml

@@ -390,4 +390,6 @@ module:
     - *iv9 # ""
   push_constant_count: 0,
   push_constants:
+  specialization_constant_count: 0,
+  specialization_constants:
 ...

tests/execution_mode/local_size_id.spv.yaml

@@ -22,4 +22,6 @@ module:
   output_variables:
   push_constant_count: 0,
   push_constants:
+  specialization_constant_count: 0,
+  specialization_constants:
 ...

tests/execution_mode/local_size_id_spec.spv.yaml

@@ -22,4 +22,6 @@ module:
   output_variables:
   push_constant_count: 0,
   push_constants:
+  specialization_constant_count: 0,
+  specialization_constants:
 ...