ISPC: Generated Headers suffix configurable with a better default

The target property `ISPC_HEADER_SUFFIX` and associated global
variable now can control the suffix used when generating the
C/C++ interoperability ISPC headers.

In addition the default suffix is now "_ispc.h" which matches the
common convention that the ISPC compiler team uses and recommends.

5 files changed, 27 insertions, 6 deletions

diff --git a/Source/cmCoreTryCompile.cxx b/Source/cmCoreTryCompile.cxx
index 77a6d4bf01..6672aa6761 100644
--- a/Source/cmCoreTryCompile.cxx
+++ b/Source/cmCoreTryCompile.cxx
@@ -201,6 +201,7 @@ std::string const kCMAKE_CUDA_ARCHITECTURES = "CMAKE_CUDA_ARCHITECTURES";
 std::string const kCMAKE_CUDA_RUNTIME_LIBRARY = "CMAKE_CUDA_RUNTIME_LIBRARY";
 std::string const kCMAKE_ENABLE_EXPORTS = "CMAKE_ENABLE_EXPORTS";
 std::string const kCMAKE_ISPC_INSTRUCTION_SETS = "CMAKE_ISPC_INSTRUCTION_SETS";
+std::string const kCMAKE_ISPC_HEADER_SUFFIX = "CMAKE_ISPC_HEADER_SUFFIX";
 std::string const kCMAKE_LINK_SEARCH_END_STATIC =
   "CMAKE_LINK_SEARCH_END_STATIC";
 std::string const kCMAKE_LINK_SEARCH_START_STATIC =
@@ -718,6 +719,7 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
       vars.insert(kCMAKE_CUDA_RUNTIME_LIBRARY);
       vars.insert(kCMAKE_ENABLE_EXPORTS);
       vars.insert(kCMAKE_ISPC_INSTRUCTION_SETS);
+      vars.insert(kCMAKE_ISPC_HEADER_SUFFIX);
       vars.insert(kCMAKE_LINK_SEARCH_END_STATIC);
       vars.insert(kCMAKE_LINK_SEARCH_START_STATIC);
       vars.insert(kCMAKE_OSX_ARCHITECTURES);
diff --git a/Source/cmLocalGenerator.cxx b/Source/cmLocalGenerator.cxx
index 368f278ab4..884d15de61 100644
--- a/Source/cmLocalGenerator.cxx
+++ b/Source/cmLocalGenerator.cxx
@@ -2426,9 +2426,12 @@ void cmLocalGenerator::AddISPCDependencies(cmGeneratorTarget* target)
     return;
   }
 
-  std::vector<std::string> ispcSuffixes =
+  cmProp ispcHeaderSuffixProp = target->GetProperty("ISPC_HEADER_SUFFIX");
+  assert(ispcHeaderSuffixProp != nullptr);
+
+  std::vector<std::string> ispcArchSuffixes =
     detail::ComputeISPCObjectSuffixes(target);
-  const bool extra_objects = (ispcSuffixes.size() > 1);
+  const bool extra_objects = (ispcArchSuffixes.size() > 1);
 
   std::vector<std::string> configsList =
     this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
@@ -2451,14 +2454,19 @@ void cmLocalGenerator::AddISPCDependencies(cmGeneratorTarget* target)
       const std::string& lang = sf->GetLanguage();
       if (lang == "ISPC") {
         std::string const& objectName = target->GetObjectName(sf);
+
+        // Drop both ".obj" and the source file extension
         std::string ispcSource =
           cmSystemTools::GetFilenameWithoutLastExtension(objectName);
+        ispcSource =
+          cmSystemTools::GetFilenameWithoutLastExtension(ispcSource);
 
-        auto headerPath = cmStrCat(headerDir, '/', ispcSource, ".h");
+        auto headerPath =
+          cmStrCat(headerDir, '/', ispcSource, *ispcHeaderSuffixProp);
         target->AddISPCGeneratedHeader(headerPath, config);
         if (extra_objects) {
           std::vector<std::string> objs = detail::ComputeISPCExtraObjects(
-            objectName, rootObjectDir, ispcSuffixes);
+            objectName, rootObjectDir, ispcArchSuffixes);
           target->AddISPCGeneratedObject(std::move(objs), config);
         }
       }
diff --git a/Source/cmMakefileTargetGenerator.cxx b/Source/cmMakefileTargetGenerator.cxx
index 3776fecc70..c6d6c9946f 100644
--- a/Source/cmMakefileTargetGenerator.cxx
+++ b/Source/cmMakefileTargetGenerator.cxx
@@ -591,6 +591,11 @@ void cmMakefileTargetGenerator::WriteObjectRuleFiles(
   if (lang == "ISPC") {
     std::string ispcSource =
       cmSystemTools::GetFilenameWithoutLastExtension(objectName);
+    ispcSource = cmSystemTools::GetFilenameWithoutLastExtension(ispcSource);
+
+    cmProp ispcSuffixProp =
+      this->GeneratorTarget->GetProperty("ISPC_HEADER_SUFFIX");
+    assert(ispcSuffixProp != nullptr);
 
     std::string directory = this->GeneratorTarget->GetObjectDirectory(config);
     if (cmProp prop =
@@ -598,7 +603,7 @@ void cmMakefileTargetGenerator::WriteObjectRuleFiles(
       directory =
         cmStrCat(this->LocalGenerator->GetBinaryDirectory(), '/', *prop);
     }
-    ispcHeaderRelative = cmStrCat(directory, '/', ispcSource, ".h");
+    ispcHeaderRelative = cmStrCat(directory, '/', ispcSource, *ispcSuffixProp);
     ispcHeaderForShell = this->LocalGenerator->ConvertToOutputFormat(
       ispcHeaderRelative, cmOutputConverter::SHELL);
   }
diff --git a/Source/cmNinjaTargetGenerator.cxx b/Source/cmNinjaTargetGenerator.cxx
index 662399e216..d41cbd286a 100644
--- a/Source/cmNinjaTargetGenerator.cxx
+++ b/Source/cmNinjaTargetGenerator.cxx
@@ -1374,6 +1374,11 @@ void cmNinjaTargetGenerator::WriteObjectBuildStatement(
       this->GeneratorTarget->GetObjectName(source);
     std::string ispcSource =
       cmSystemTools::GetFilenameWithoutLastExtension(objectName);
+    ispcSource = cmSystemTools::GetFilenameWithoutLastExtension(ispcSource);
+
+    cmProp ispcSuffixProp =
+      this->GeneratorTarget->GetProperty("ISPC_HEADER_SUFFIX");
+    assert(ispcSuffixProp != nullptr);
 
     std::string ispcHeaderDirectory =
       this->GeneratorTarget->GetObjectDirectory(config);
@@ -1384,7 +1389,7 @@ void cmNinjaTargetGenerator::WriteObjectBuildStatement(
     }
 
     std::string ispcHeader =
-      cmStrCat(ispcHeaderDirectory, '/', ispcSource, ".h");
+      cmStrCat(ispcHeaderDirectory, '/', ispcSource, *ispcSuffixProp);
     ispcHeader = this->ConvertToNinjaPath(ispcHeader);
 
     // Make sure ninja knows what command generates the header
diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx
index d26de9cd4b..bda2b30b16 100644
--- a/Source/cmTarget.cxx
+++ b/Source/cmTarget.cxx
@@ -369,6 +369,7 @@ cmTarget::cmTarget(std::string const& name, cmStateEnums::TargetType type,
     initProp("JOB_POOL_PRECOMPILE_HEADER");
     initProp("ISPC_COMPILER_LAUNCHER");
     initProp("ISPC_HEADER_DIRECTORY");
+    initPropValue("ISPC_HEADER_SUFFIX", "_ispc.h");
     initProp("ISPC_INSTRUCTION_SETS");
     initProp("LINK_SEARCH_START_STATIC");
     initProp("LINK_SEARCH_END_STATIC");