[DirectX] Detect resources with identical overlapping binding

This change uses resource name during DXIL resource binding analysis to detect
when two (or more) resources have identical overlapping binding.

The DXIL resource analysis just detects that there is a problem with the binding
and sets the `hasOverlappingBinding` flag. Full error reporting will happen
later in DXILPostOptimizationValidation pass (#110723).

Author: hekota

llvm/lib/Analysis/DXILResource.cpp

@@ -892,10 +892,11 @@ void DXILResourceBindingInfo::populate(Module &M, DXILResourceTypeMap &DRTM) {
     uint32_t Space;
     uint32_t LowerBound;
     uint32_t UpperBound;
+    Value *Name;
     Binding(ResourceClass RC, uint32_t Space, uint32_t LowerBound,
-            uint32_t UpperBound)
-        : RC(RC), Space(Space), LowerBound(LowerBound), UpperBound(UpperBound) {
-    }
+            uint32_t UpperBound, Value *Name)
+        : RC(RC), Space(Space), LowerBound(LowerBound), UpperBound(UpperBound),
+          Name(Name) {}
   };
   SmallVector<Binding> Bindings;
 
@@ -920,14 +921,15 @@ void DXILResourceBindingInfo::populate(Module &M, DXILResourceTypeMap &DRTM) {
               cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
           int32_t Size =
               cast<ConstantInt>(CI->getArgOperand(2))->getZExtValue();
+          Value *Name = CI->getArgOperand(5);
 
           // negative size means unbounded resource array;
           // upper bound register overflow should be detected in Sema
           assert((Size < 0 || (unsigned)LowerBound + Size - 1 <= UINT32_MAX) &&
                  "upper bound register overflow");
           uint32_t UpperBound = Size < 0 ? UINT32_MAX : LowerBound + Size - 1;
           Bindings.emplace_back(RTI.getResourceClass(), Space, LowerBound,
-                                UpperBound);
+                                UpperBound, Name);
         }
       break;
     }
@@ -946,8 +948,9 @@ void DXILResourceBindingInfo::populate(Module &M, DXILResourceTypeMap &DRTM) {
 
   // remove duplicates
   Binding *NewEnd = llvm::unique(Bindings, [](auto &LHS, auto &RHS) {
-    return std::tie(LHS.RC, LHS.Space, LHS.LowerBound, LHS.UpperBound) ==
-           std::tie(RHS.RC, RHS.Space, RHS.LowerBound, RHS.UpperBound);
+    return std::tie(LHS.RC, LHS.Space, LHS.LowerBound, LHS.UpperBound,
+                    LHS.Name) == std::tie(RHS.RC, RHS.Space, RHS.LowerBound,
+                                          RHS.UpperBound, RHS.Name);
   });
   if (NewEnd != Bindings.end())
     Bindings.erase(NewEnd);
@@ -987,8 +990,6 @@ void DXILResourceBindingInfo::populate(Module &M, DXILResourceTypeMap &DRTM) {
       if (B.UpperBound < UINT32_MAX)
         S->FreeRanges.emplace_back(B.UpperBound + 1, UINT32_MAX);
     } else {
-      // FIXME: This only detects overlapping bindings that are not an exact
-      // match (llvm/llvm-project#110723)
       OverlappingBinding = true;
       if (B.UpperBound < UINT32_MAX)
         LastFreeRange.LowerBound =

llvm/unittests/Target/DirectX/ResourceBindingAnalysisTests.cpp

@@ -167,7 +167,6 @@ TEST_F(ResourceBindingAnalysisTest, TestUnboundedAndOverlap) {
   // StructuredBuffer<float> C[]  : register(t0, space2);
   // StructuredBuffer<float> D    : register(t4, space2); /* overlapping */
   StringRef Assembly = R"(
-%__cblayout_CB = type <{ i32 }>
 define void @main() {
 entry:
   %handleA = call target("dx.RawBuffer", float, 0, 0) @llvm.dx.resource.handlefrombinding(i32 0, i32 5, i32 -1, i32 10, i1 false, ptr null)
@@ -198,11 +197,12 @@ TEST_F(ResourceBindingAnalysisTest, TestExactOverlap) {
   // StructuredBuffer<float> A  : register(t5);
   // StructuredBuffer<float> B  : register(t5);
   StringRef Assembly = R"(
-%__cblayout_CB = type <{ i32 }>
+@A.str = private unnamed_addr constant [2 x i8] c"A\00", align 1
+@B.str = private unnamed_addr constant [2 x i8] c"B\00", align 1
 define void @main() {
 entry:
-  %handleA = call target("dx.RawBuffer", float, 0, 0) @llvm.dx.resource.handlefrombinding(i32 0, i32 5, i32 1, i32 0, i1 false, ptr null)
-  %handleB = call target("dx.RawBuffer", float, 0, 0) @llvm.dx.resource.handlefrombinding(i32 0, i32 5, i32 1, i32 0, i1 false, ptr null)
+  %handleA = call target("dx.RawBuffer", float, 0, 0) @llvm.dx.resource.handlefrombinding(i32 0, i32 5, i32 1, i32 0, i1 false, ptr @A.str)
+  %handleB = call target("dx.RawBuffer", float, 0, 0) @llvm.dx.resource.handlefrombinding(i32 0, i32 5, i32 1, i32 0, i1 false, ptr @B.str)
   ret void
 }
   )";
@@ -213,9 +213,7 @@ define void @main() {
       MAM->getResult<DXILResourceBindingAnalysis>(*M);
 
   EXPECT_EQ(false, DRBI.hasImplicitBinding());
-  // FIXME (XFAIL): detecting overlap of two resource with identical binding
-  // is not yet supported (llvm/llvm-project#110723).
-  EXPECT_EQ(false, DRBI.hasOverlappingBinding());
+  EXPECT_EQ(true, DRBI.hasOverlappingBinding());
 
   DXILResourceBindingInfo::BindingSpaces &SRVSpaces =
       DRBI.getBindingSpaces(ResourceClass::SRV);