Support new-style kernels with no output and no input.

Such kernels get the definition of their iteration space solely through LaunchOptions.

No runtime testing of no-allocation kernels yet.

Bug 19950069

Change-Id: I452f948967d52e0ce8998628d554ab188cae9116

10 files changed, 46 insertions, 26 deletions

diff --git a/slang_rs_export_foreach.cpp b/slang_rs_export_foreach.cpp
index d3ba154..026e6fc 100644
--- a/slang_rs_export_foreach.cpp
+++ b/slang_rs_export_foreach.cpp
@@ -276,12 +276,14 @@ bool RSExportForEach::validateAndConstructKernelParams(
   }
 
   // Check that we have at least one allocation to use for dimensions.
-  if (valid && mIns.empty() && !mHasReturnType) {
+  if (valid && mIns.empty() && !mHasReturnType && Context->getTargetAPI() < SLANG_23_TARGET_API) {
     Context->ReportError(FD->getLocation(),
-                         "Compute kernel %0() must have at least one "
+                         "Compute kernel %0() targeting SDK levels "
+                         "%1-%2 must have at least one "
                          "input parameter or a non-void return "
                          "type")
-        << FD->getName();
+        << FD->getName() << SLANG_MINIMUM_TARGET_API
+        << (SLANG_23_TARGET_API - 1);
     valid = false;
   }
 
diff --git a/slang_rs_reflection.cpp b/slang_rs_reflection.cpp
index dfa6e75..f1d9d3d 100644
--- a/slang_rs_reflection.cpp
+++ b/slang_rs_reflection.cpp
@@ -692,17 +692,18 @@ void RSReflectionJava::genExportForEach(const RSExportForEach *EF) {
 
   // forEach_*()
   ArgTy Args;
-
-  slangAssert(EF->getNumParameters() > 0 || EF->hasReturn());
+  bool HasAllocation = false; // at least one in/out allocation?
 
   const RSExportForEach::InVec     &Ins     = EF->getIns();
   const RSExportForEach::InTypeVec &InTypes = EF->getInTypes();
   const RSExportType               *OET     = EF->getOutType();
 
   if (Ins.size() == 1) {
+    HasAllocation = true;
     Args.push_back(std::make_pair("Allocation", "ain"));
 
   } else if (Ins.size() > 1) {
+    HasAllocation = true;
     for (RSExportForEach::InIter BI = Ins.begin(), EI = Ins.end(); BI != EI;
          BI++) {
 
@@ -711,8 +712,10 @@ void RSReflectionJava::genExportForEach(const RSExportForEach *EF) {
     }
   }
 
-  if (EF->hasOut() || EF->hasReturn())
+  if (EF->hasOut() || EF->hasReturn()) {
+    HasAllocation = true;
     Args.push_back(std::make_pair("Allocation", "aout"));
+  }
 
   const RSExportRecordType *ERT = EF->getParamPacketType();
   if (ERT) {
@@ -737,34 +740,36 @@ void RSReflectionJava::genExportForEach(const RSExportForEach *EF) {
   }
 
   if (mRSContext->getTargetAPI() >= SLANG_JB_MR2_TARGET_API) {
-    startFunction(AM_Public, false, "void", "forEach_" + EF->getName(), Args);
+    if (HasAllocation) {
+      startFunction(AM_Public, false, "void", "forEach_" + EF->getName(), Args);
 
-    mOut.indent() << "forEach_" << EF->getName();
-    mOut << "(";
+      mOut.indent() << "forEach_" << EF->getName();
+      mOut << "(";
 
-    if (Ins.size() == 1) {
-      mOut << "ain, ";
+      if (Ins.size() == 1) {
+        mOut << "ain, ";
 
-    } else if (Ins.size() > 1) {
-      for (RSExportForEach::InIter BI = Ins.begin(), EI = Ins.end(); BI != EI;
-           BI++) {
+      } else if (Ins.size() > 1) {
+        for (RSExportForEach::InIter BI = Ins.begin(), EI = Ins.end(); BI != EI;
+             BI++) {
 
-        mOut << "ain_" << (*BI)->getName().str() << ", ";
+          mOut << "ain_" << (*BI)->getName().str() << ", ";
+        }
       }
-    }
 
-    if (EF->hasOut() || EF->hasReturn()) {
-      mOut << "aout, ";
-    }
+      if (EF->hasOut() || EF->hasReturn()) {
+        mOut << "aout, ";
+      }
 
-    if (EF->hasUsrData()) {
-      mOut << Args.back().second << ", ";
-    }
+      if (EF->hasUsrData()) {
+        mOut << Args.back().second << ", ";
+      }
 
-    // No clipped bounds to pass in.
-    mOut << "null);\n";
+      // No clipped bounds to pass in.
+      mOut << "null);\n";
 
-    endFunction();
+      endFunction();
+    }
 
     // Add the clipped kernel parameters to the Args list.
     Args.push_back(std::make_pair("Script.LaunchOptions", "sc"));
diff --git a/tests/F_kernel_badsig/kernel_badsig.rs b/tests/F_kernel_badsig/kernel_badsig.rs
index ab64847..394e9c9 100644
--- a/tests/F_kernel_badsig/kernel_badsig.rs
+++ b/tests/F_kernel_badsig/kernel_badsig.rs
@@ -1,3 +1,4 @@
+// -target-api 22
 #pragma version(1)
 #pragma rs java_package_name(foo)
 
diff --git a/tests/F_kernel_badsig/stderr.txt.expect b/tests/F_kernel_badsig/stderr.txt.expect
index 633158c..ca771ad 100644
--- a/tests/F_kernel_badsig/stderr.txt.expect
+++ b/tests/F_kernel_badsig/stderr.txt.expect
@@ -1 +1 @@
-kernel_badsig.rs:4:16: error: Compute kernel root() must have at least one input parameter or a non-void return type
+kernel_badsig.rs:5:16: error: Compute kernel root() targeting SDK levels 11-22 must have at least one input parameter or a non-void return type
diff --git a/tests/P_kernel_noalloc/kernel_noalloc.rs b/tests/P_kernel_noalloc/kernel_noalloc.rs
new file mode 100644
index 0000000..ab64847
--- /dev/null
+++ b/tests/P_kernel_noalloc/kernel_noalloc.rs
@@ -0,0 +1,6 @@
+#pragma version(1)
+#pragma rs java_package_name(foo)
+
+void RS_KERNEL root(uint32_t x) {
+}
+
diff --git a/tests/P_kernel_noalloc/stderr.txt.expect b/tests/P_kernel_noalloc/stderr.txt.expect
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/tests/P_kernel_noalloc/stderr.txt.expect
diff --git a/tests/P_kernel_noalloc/stdout.txt.expect b/tests/P_kernel_noalloc/stdout.txt.expect
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/tests/P_kernel_noalloc/stdout.txt.expect
diff --git a/tests/P_kernel_noalloc_noarg/kernel_noalloc_noarg.rs b/tests/P_kernel_noalloc_noarg/kernel_noalloc_noarg.rs
new file mode 100644
index 0000000..e1ccb09
--- /dev/null
+++ b/tests/P_kernel_noalloc_noarg/kernel_noalloc_noarg.rs
@@ -0,0 +1,6 @@
+#pragma version(1)
+#pragma rs java_package_name(foo)
+
+void RS_KERNEL root() {
+}
+
diff --git a/tests/P_kernel_noalloc_noarg/stderr.txt.expect b/tests/P_kernel_noalloc_noarg/stderr.txt.expect
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/tests/P_kernel_noalloc_noarg/stderr.txt.expect
diff --git a/tests/P_kernel_noalloc_noarg/stdout.txt.expect b/tests/P_kernel_noalloc_noarg/stdout.txt.expect
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/tests/P_kernel_noalloc_noarg/stdout.txt.expect