From cb009b3862dc2d5d93a0831c65ac112a72c1645b Mon Sep 17 00:00:00 2001
From: Ehsan Nasiri <ehsann@google.com>
Date: Tue, 17 Jan 2017 15:10:43 -0500
Subject: [PATCH] Fixes issue #497.

The Linkage Attributes Decoration cannot be applied to functions
targeted by an OpEntryPoint instruction.
---
 source/validate_decorations.cpp  | 15 +++++++++++++++
 test/val/val_decoration_test.cpp | 23 +++++++++++++++++++++++
 2 files changed, 38 insertions(+)

diff --git a/source/validate_decorations.cpp b/source/validate_decorations.cpp
index d7e56e6..134dea8 100644
--- a/source/validate_decorations.cpp
+++ b/source/validate_decorations.cpp
@@ -107,8 +107,23 @@ spv_result_t ValidateDecorations(ValidationState_t& vstate) {
                 "BuiltIn, consumed per entry-point. Entry Point id "
              << entry_point << " does not meet this requirement.";
     }
+    // The LinkageAttributes Decoration cannot be applied to functions targeted
+    // by an OpEntryPoint instruction
+    for (auto& decoration : vstate.id_decorations(entry_point)) {
+      if (SpvDecorationLinkageAttributes == decoration.dec_type()) {
+        const char* linkage_name =
+            reinterpret_cast<const char*>(&decoration.params()[0]);
+        return vstate.diag(SPV_ERROR_INVALID_BINARY)
+               << "The LinkageAttributes Decoration (Linkage name: "
+               << linkage_name << ") cannot be applied to function id "
+               << entry_point
+               << " because it is targeted by an OpEntryPoint instruction.";
+      }
+    }
   }
 
+  // TODO: Refactor this function into smaller pieces.
+
   return SPV_SUCCESS;
 }
 
diff --git a/test/val/val_decoration_test.cpp b/test/val/val_decoration_test.cpp
index 8315959..eab9166 100644
--- a/test/val/val_decoration_test.cpp
+++ b/test/val/val_decoration_test.cpp
@@ -337,5 +337,28 @@ TEST_F(ValidateDecorations, NoBuiltInObjectsConsumedByOpEntryPointGood) {
   EXPECT_EQ(SPV_SUCCESS, ValidateAndRetrieveValidationState());
 }
 
+TEST_F(ValidateDecorations, EntryPointFunctionHasLinkageAttributeBad) {
+  string spirv = R"(
+      OpCapability Shader
+      OpCapability Linkage
+      OpMemoryModel Logical GLSL450
+      OpEntryPoint GLCompute %main "main"
+      OpDecorate %main LinkageAttributes "import_main" Import
+%1 = OpTypeVoid
+%2 = OpTypeFunction %1
+%main = OpFunction %1 None %2
+%4 = OpLabel
+     OpReturn
+     OpFunctionEnd
+)";
+  CompileSuccessfully(spirv.c_str());
+  EXPECT_EQ(SPV_ERROR_INVALID_BINARY, ValidateInstructions());
+  EXPECT_THAT(
+      getDiagnosticString(),
+      HasSubstr("The LinkageAttributes Decoration (Linkage name: import_main) "
+                "cannot be applied to function id 1 because it is targeted by "
+                "an OpEntryPoint instruction."));
+}
+
 }  // anonymous namespace
 
-- 
2.7.4