[clang] 5dbb92d - [HLSL] CodeGen HLSL Resource annotations

[Chris Bieneman via cfe-commits]

Author: Chris Bieneman
Date: 2022-08-01T11:19:43-05:00
New Revision: 5dbb92d8cdf751d5960225e874c27d19597fa65e

URL: https://github.com/llvm/llvm-project/commit/5dbb92d8cdf751d5960225e874c27d19597fa65e
DIFF: https://github.com/llvm/llvm-project/commit/5dbb92d8cdf751d5960225e874c27d19597fa65e.diff

LOG: [HLSL] CodeGen HLSL Resource annotations

HLSL Resource types need special annotations that the backend will use
to build out metadata and resource annotations that are required by
DirectX and Vulkan drivers in order to provide correct data bindings
for shader exeuction.

This patch adds some of the required data for unordered-access-views
(UAV) resource binding into the module flags. This data will evolve
over time to cover all the required use cases, but this should get
things started.

Depends on D130018.

Differential Revision: https://reviews.llvm.org/D130019

Added: 
    clang/test/CodeGenHLSL/builtins/RWBuffer-annotations.hlsl

Modified: 
    clang/lib/CodeGen/CGDeclCXX.cpp
    clang/lib/CodeGen/CGHLSLRuntime.cpp
    clang/lib/CodeGen/CGHLSLRuntime.h

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CGDeclCXX.cpp b/clang/lib/CodeGen/CGDeclCXX.cpp
index 949112c63cc9e..620af1e633b73 100644
--- a/clang/lib/CodeGen/CGDeclCXX.cpp
+++ b/clang/lib/CodeGen/CGDeclCXX.cpp
@@ -11,6 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "CGCXXABI.h"
+#include "CGHLSLRuntime.h"
 #include "CGObjCRuntime.h"
 #include "CGOpenMPRuntime.h"
 #include "CodeGenFunction.h"
@@ -977,6 +978,9 @@ void CodeGenFunction::GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn,
     EmitCXXGlobalVarDeclInit(*D, Addr, PerformInit);
   }
 
+  if (getLangOpts().HLSL)
+    CGM.getHLSLRuntime().annotateHLSLResource(D, Addr);
+
   FinishFunction();
 }
 

diff  --git a/clang/lib/CodeGen/CGHLSLRuntime.cpp b/clang/lib/CodeGen/CGHLSLRuntime.cpp
index 7dfcc65969a86..3321d4ad0afb5 100644
--- a/clang/lib/CodeGen/CGHLSLRuntime.cpp
+++ b/clang/lib/CodeGen/CGHLSLRuntime.cpp
@@ -20,6 +20,7 @@
 
 using namespace clang;
 using namespace CodeGen;
+using namespace hlsl;
 using namespace llvm;
 
 namespace {
@@ -50,3 +51,38 @@ void CGHLSLRuntime::finishCodeGen() {
   llvm::Module &M = CGM.getModule();
   addDxilValVersion(TargetOpts.DxilValidatorVersion, M);
 }
+
+void CGHLSLRuntime::annotateHLSLResource(const VarDecl *D, GlobalVariable *GV) {
+  const Type *Ty = D->getType()->getPointeeOrArrayElementType();
+  if (!Ty)
+    return;
+  const auto *RD = Ty->getAsCXXRecordDecl();
+  if (!RD)
+    return;
+  const auto *Attr = RD->getAttr<HLSLResourceAttr>();
+  if (!Attr)
+    return;
+
+  HLSLResourceAttr::ResourceClass RC = Attr->getResourceType();
+  uint32_t Counter = ResourceCounters[static_cast<uint32_t>(RC)]++;
+
+  NamedMDNode *ResourceMD = nullptr;
+  switch (RC) {
+  case HLSLResourceAttr::ResourceClass::UAV:
+    ResourceMD = CGM.getModule().getOrInsertNamedMetadata("hlsl.uavs");
+    break;
+  default:
+    assert(false && "Unsupported buffer type!");
+    return;
+  }
+
+  assert(ResourceMD != nullptr &&
+         "ResourceMD must have been set by the switch above.");
+
+  auto &Ctx = CGM.getModule().getContext();
+  IRBuilder<> B(Ctx);
+  QualType QT(Ty, 0);
+  ResourceMD->addOperand(MDNode::get(
+      Ctx, {ValueAsMetadata::get(GV), MDString::get(Ctx, QT.getAsString()),
+            ConstantAsMetadata::get(B.getInt32(Counter))}));
+}

diff  --git a/clang/lib/CodeGen/CGHLSLRuntime.h b/clang/lib/CodeGen/CGHLSLRuntime.h
index 268810f2ec9e6..5953be4117f94 100644
--- a/clang/lib/CodeGen/CGHLSLRuntime.h
+++ b/clang/lib/CodeGen/CGHLSLRuntime.h
@@ -15,7 +15,16 @@
 #ifndef LLVM_CLANG_LIB_CODEGEN_CGHLSLRUNTIME_H
 #define LLVM_CLANG_LIB_CODEGEN_CGHLSLRUNTIME_H
 
+#include "clang/Basic/HLSLRuntime.h"
+
+namespace llvm {
+class Value;
+class GlobalVariable;
+} // namespace llvm
 namespace clang {
+class CallExpr;
+class Type;
+class VarDecl;
 
 namespace CodeGen {
 
@@ -24,11 +33,15 @@ class CodeGenModule;
 class CGHLSLRuntime {
 protected:
   CodeGenModule &CGM;
+  uint32_t ResourceCounters[static_cast<uint32_t>(
+      hlsl::ResourceClass::NumClasses)] = {0};
 
 public:
   CGHLSLRuntime(CodeGenModule &CGM) : CGM(CGM) {}
   virtual ~CGHLSLRuntime() {}
 
+  void annotateHLSLResource(const VarDecl *D, llvm::GlobalVariable *GV);
+
   void finishCodeGen();
 };
 

diff  --git a/clang/test/CodeGenHLSL/builtins/RWBuffer-annotations.hlsl b/clang/test/CodeGenHLSL/builtins/RWBuffer-annotations.hlsl
new file mode 100644
index 0000000000000..4d12fa197f5e2
--- /dev/null
+++ b/clang/test/CodeGenHLSL/builtins/RWBuffer-annotations.hlsl
@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-compute -x hlsl -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s 
+
+RWBuffer<float> Buffer1;
+RWBuffer<vector<float, 4> > BufferArray[4];
+
+[numthreads(1,1,1)]
+void main() {
+}
+
+// CHECK: !hlsl.uavs = !{![[Single:[0-9]+]], ![[Array:[0-9]+]]}
+// CHECK-DAG: ![[Single]] = !{ptr @"?Buffer1@@3V?$RWBuffer at M@hlsl@@A", !"RWBuffer<float>", i32 0}
+// CHECK-DAG: ![[Array]] = !{ptr @"?BufferArray@@3PAV?$RWBuffer at T?$__vector at M$03 at __clang@@@hlsl@@A", !"RWBuffer<vector<float, 4> >", i32 1}