[WebAssembly] Add path to PIC mode for wasm tables (llvm#67545)

Currently tables cannot be shared between compilation units, therefore
no special treatment is needed for tables.

Fixes llvm#65191

Author: pmatos

llvm/lib/Target/WebAssembly/Utils/WebAssemblyTypeUtilities.cpp

@@ -71,8 +71,7 @@ void WebAssembly::wasmSymbolSetType(MCSymbolWasm *Sym, const Type *GlobalVT,
   // that is a reference type.
   wasm::ValType ValTy;
   bool IsTable = false;
-  if (GlobalVT->isArrayTy() && WebAssembly::isWebAssemblyReferenceType(
-                                   GlobalVT->getArrayElementType())) {
+  if (WebAssembly::isWebAssemblyTableType(GlobalVT)) {
     IsTable = true;
     const Type *ElTy = GlobalVT->getArrayElementType();
     if (WebAssembly::isWebAssemblyExternrefType(ElTy))

llvm/lib/Target/WebAssembly/Utils/WebAssemblyTypeUtilities.h

@@ -28,21 +28,29 @@ namespace WebAssembly {
 
 /// Return true if this is a WebAssembly Externref Type.
 inline bool isWebAssemblyExternrefType(const Type *Ty) {
-  return Ty->getPointerAddressSpace() ==
-         WebAssembly::WasmAddressSpace::WASM_ADDRESS_SPACE_EXTERNREF;
+  return Ty->isPointerTy() &&
+         Ty->getPointerAddressSpace() ==
+             WebAssembly::WasmAddressSpace::WASM_ADDRESS_SPACE_EXTERNREF;
 }
 
 /// Return true if this is a WebAssembly Funcref Type.
 inline bool isWebAssemblyFuncrefType(const Type *Ty) {
-  return Ty->getPointerAddressSpace() ==
-         WebAssembly::WasmAddressSpace::WASM_ADDRESS_SPACE_FUNCREF;
+  return Ty->isPointerTy() &&
+         Ty->getPointerAddressSpace() ==
+             WebAssembly::WasmAddressSpace::WASM_ADDRESS_SPACE_FUNCREF;
 }
 
 /// Return true if this is a WebAssembly Reference Type.
 inline bool isWebAssemblyReferenceType(const Type *Ty) {
   return isWebAssemblyExternrefType(Ty) || isWebAssemblyFuncrefType(Ty);
 }
 
+/// Return true if the table represents a WebAssembly table type.
+inline bool isWebAssemblyTableType(const Type *Ty) {
+  return Ty->isArrayTy() &&
+         isWebAssemblyReferenceType(Ty->getArrayElementType());
+}
+
 // Convert StringRef to ValType / HealType / BlockType
 
 MVT parseMVT(StringRef Type);

llvm/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp

@@ -1724,8 +1724,11 @@ SDValue WebAssemblyTargetLowering::LowerGlobalAddress(SDValue Op,
     fail(DL, DAG, "Invalid address space for WebAssembly target");
 
   unsigned OperandFlags = 0;
-  if (isPositionIndependent()) {
-    const GlobalValue *GV = GA->getGlobal();
+  const GlobalValue *GV = GA->getGlobal();
+  // Since WebAssembly tables cannot yet be shared accross modules, we don't
+  // need special treatment for tables in PIC mode.
+  if (isPositionIndependent() &&
+      !WebAssembly::isWebAssemblyTableType(GV->getValueType())) {
     if (getTargetMachine().shouldAssumeDSOLocal(*GV->getParent(), GV)) {
       MachineFunction &MF = DAG.getMachineFunction();
       MVT PtrVT = getPointerTy(MF.getDataLayout());

llvm/test/MC/WebAssembly/reloc-pic.s

@@ -1,5 +1,5 @@
-# RUN: llvm-mc -triple=wasm32-unknown-unknown -filetype=obj < %s | obj2yaml | FileCheck %s
-# RUN: llvm-mc -triple=wasm32-unknown-unknown -mattr=+reference-types -filetype=obj < %s | obj2yaml | FileCheck --check-prefix=REF %s
+# RUN: sed -e '/^REF-/d' %s | llvm-mc -triple=wasm32-unknown-unknown -filetype=obj | obj2yaml | FileCheck %s
+# RUN: sed -e 's/^REF-//g' %s | llvm-mc -triple=wasm32-unknown-unknown -mattr=+reference-types -filetype=obj | obj2yaml | FileCheck --check-prefix=REF %s
 
 # Verify that @GOT relocation entryes result in R_WASM_GLOBAL_INDEX_LEB against
 # against the corrsponding function or data symbol and that the corresponding
@@ -50,6 +50,9 @@ hidden_func:
 #.hidden hidden_data
 .size default_data, 4
 
+REF-mytable:
+REF-.tabletype mytable, externref
+
 # CHECK:      --- !WASM
 # CHECK-NEXT: FileHeader:
 # CHECK-NEXT:   Version:         0x1
@@ -209,6 +212,11 @@ hidden_func:
 # CHECK-NEXT:         Function:        5
 # REF:              - Index:           10
 # REF-NEXT:           Kind:            TABLE
+# REF-NEXT:           Name:            mytable
+# REF-NEXT:           Flags:           [ BINDING_LOCAL ]
+# REF-NEXT:           Table:           1
+# REF-NEXT:         - Index:           11
+# REF-NEXT:           Kind:            TABLE
 # REF-NEXT:           Name:            __indirect_function_table
 # REF-NEXT:           Flags:           [ UNDEFINED, NO_STRIP ]
 # REF-NEXT:           Table:           0