[WebAssembly] Add multivalue and tail-call target features

Summary:
These features will both be implemented soon, so I thought I would
save time by adding the boilerplate for both of them at the same time.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D62047

llvm-svn: 361516

clang/include/clang/Driver/Options.td

@@ -2185,6 +2185,10 @@ def mbulk_memory : Flag<["-"], "mbulk-memory">, Group<m_wasm_Features_Group>;
 def mno_bulk_memory : Flag<["-"], "mno-bulk-memory">, Group<m_wasm_Features_Group>;
 def mmutable_globals : Flag<["-"], "mmutable-globals">, Group<m_wasm_Features_Group>;
 def mno_mutable_globals : Flag<["-"], "mno-mutable-globals">, Group<m_wasm_Features_Group>;
+def mmultivalue : Flag<["-"], "mmultivalue">, Group<m_wasm_Features_Group>;
+def mno_multivalue : Flag<["-"], "mno-multivalue">, Group<m_wasm_Features_Group>;
+def mtail_call : Flag<["-"], "mtail-call">, Group<m_wasm_Features_Group>;
+def mno_tail_call : Flag<["-"], "mno-tail-call">, Group<m_wasm_Features_Group>;
 
 def mamdgpu_debugger_abi : Joined<["-"], "mamdgpu-debugger-abi=">,
   Flags<[HelpHidden]>,

clang/lib/Basic/Targets/WebAssembly.cpp

@@ -43,6 +43,8 @@ bool WebAssemblyTargetInfo::hasFeature(StringRef Feature) const {
       .Case("bulk-memory", HasBulkMemory)
       .Case("atomics", HasAtomics)
       .Case("mutable-globals", HasMutableGlobals)
+      .Case("multivalue", HasMultivalue)
+      .Case("tail-call", HasTailCall)
       .Default(false);
 }
 
@@ -74,6 +76,10 @@ void WebAssemblyTargetInfo::getTargetDefines(const LangOptions &Opts,
     Builder.defineMacro("__wasm_atomics__");
   if (HasMutableGlobals)
     Builder.defineMacro("__wasm_mutable_globals__");
+  if (HasMultivalue)
+    Builder.defineMacro("__wasm_multivalue__");
+  if (HasTailCall)
+    Builder.defineMacro("__wasm_tail_call__");
 }
 
 void WebAssemblyTargetInfo::setSIMDLevel(llvm::StringMap<bool> &Features,
@@ -116,6 +122,10 @@ bool WebAssemblyTargetInfo::initFeatureMap(
     Features["atomics"] = true;
   if (HasMutableGlobals)
     Features["mutable-globals"] = true;
+  if (HasMultivalue)
+    Features["multivalue"] = true;
+  if (HasTailCall)
+    Features["tail-call"] = true;
 
   return TargetInfo::initFeatureMap(Features, Diags, CPU, FeaturesVec);
 }
@@ -187,6 +197,22 @@ bool WebAssemblyTargetInfo::handleTargetFeatures(
       HasMutableGlobals = false;
       continue;
     }
+    if (Feature == "+multivalue") {
+      HasMultivalue = true;
+      continue;
+    }
+    if (Feature == "-multivalue") {
+      HasMultivalue = false;
+      continue;
+    }
+    if (Feature == "+tail-call") {
+      HasTailCall = true;
+      continue;
+    }
+    if (Feature == "-tail-call") {
+      HasTailCall = false;
+      continue;
+    }
 
     Diags.Report(diag::err_opt_not_valid_with_opt)
         << Feature << "-target-feature";

clang/lib/Basic/Targets/WebAssembly.h

@@ -36,6 +36,8 @@ class LLVM_LIBRARY_VISIBILITY WebAssemblyTargetInfo : public TargetInfo {
   bool HasBulkMemory = false;
   bool HasAtomics = false;
   bool HasMutableGlobals = false;
+  bool HasMultivalue = false;
+  bool HasTailCall = false;
 
 public:
   explicit WebAssemblyTargetInfo(const llvm::Triple &T, const TargetOptions &)

clang/test/Preprocessor/wasm-target-features.c

@@ -79,6 +79,24 @@
 //
 // MUTABLE-GLOBALS:#define __wasm_mutable_globals__ 1{{$}}
 
+// RUN: %clang -E -dM %s -o - 2>&1 \
+// RUN:     -target wasm32-unknown-unknown -mmultivalue \
+// RUN:   | FileCheck %s -check-prefix=MULTIVALUE
+// RUN: %clang -E -dM %s -o - 2>&1 \
+// RUN:     -target wasm64-unknown-unknown -mmultivalue \
+// RUN:   | FileCheck %s -check-prefix=MULTIVALUE
+//
+// MULTIVALUE:#define __wasm_multivalue__ 1{{$}}
+
+// RUN: %clang -E -dM %s -o - 2>&1 \
+// RUN:     -target wasm32-unknown-unknown -mtail-call \
+// RUN:   | FileCheck %s -check-prefix=TAIL-CALL
+// RUN: %clang -E -dM %s -o - 2>&1 \
+// RUN:     -target wasm64-unknown-unknown -mtail-call \
+// RUN:   | FileCheck %s -check-prefix=TAIL-CALL
+//
+// TAIL-CALL:#define __wasm_tail_call__ 1{{$}}
+
 // RUN: %clang -E -dM %s -o - 2>&1 \
 // RUN:     -target wasm32-unknown-unknown -mcpu=mvp \
 // RUN:   | FileCheck %s -check-prefix=MVP
@@ -94,6 +112,8 @@
 // MVP-NOT:#define __wasm_bulk_memory__
 // MVP-NOT:#define __wasm_atomics__
 // MVP-NOT:#define __wasm_mutable_globals__
+// MVP-NOT:#define __wasm_multivalue__
+// MVP-NOT:#define __wasm_tail_call__
 
 // RUN: %clang -E -dM %s -o - 2>&1 \
 // RUN:     -target wasm32-unknown-unknown -mcpu=bleeding-edge \
@@ -108,6 +128,8 @@
 // BLEEDING-EDGE-DAG:#define __wasm_atomics__ 1{{$}}
 // BLEEDING-EDGE-DAG:#define __wasm_mutable_globals__ 1{{$}}
 // BLEEDING-EDGE-NOT:#define __wasm_unimplemented_simd128__ 1{{$}}
+// BLEEDING-EDGE-NOT:#define __wasm_multivalue__ 1{{$}}
+// BLEEDING-EDGE-NOT:#define __wasm_tail_call__ 1{{$}}
 
 // RUN: %clang -E -dM %s -o - 2>&1 \
 // RUN:     -target wasm32-unknown-unknown -mcpu=bleeding-edge -mno-simd128 \

llvm/lib/Target/WebAssembly/WebAssembly.td

@@ -33,6 +33,7 @@ def FeatureUnimplementedSIMD128 :
 
 def FeatureAtomics : SubtargetFeature<"atomics", "HasAtomics", "true",
                                       "Enable Atomics">;
+
 def FeatureNontrappingFPToInt :
       SubtargetFeature<"nontrapping-fptoint",
                        "HasNontrappingFPToInt", "true",
@@ -43,6 +44,11 @@ def FeatureSignExt :
                        "HasSignExt", "true",
                        "Enable sign extension operators">;
 
+def FeatureTailCall :
+      SubtargetFeature<"tail-call",
+                       "HasTailCall", "true",
+                       "Enable tail call instructions">;
+
 def FeatureExceptionHandling :
       SubtargetFeature<"exception-handling", "HasExceptionHandling", "true",
                        "Enable Wasm exception handling">;
@@ -51,6 +57,11 @@ def FeatureBulkMemory :
       SubtargetFeature<"bulk-memory", "HasBulkMemory", "true",
                        "Enable bulk memory operations">;
 
+def FeatureMultivalue :
+      SubtargetFeature<"multivalue",
+                       "HasMultivalue", "true",
+                       "Enable multivalue blocks, instructions, and functions">;
+
 def FeatureMutableGlobals :
       SubtargetFeature<"mutable-globals", "HasMutableGlobals", "true",
                        "Enable mutable globals">;

llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td

@@ -34,6 +34,10 @@ def HasAtomics :
     Predicate<"Subtarget->hasAtomics()">,
     AssemblerPredicate<"FeatureAtomics", "atomics">;
 
+def HasMultivalue :
+    Predicate<"Subtarget->hasMultivalue()">,
+    AssemblerPredicate<"FeatureMultivalue", "multivalue">;
+
 def HasNontrappingFPToInt :
     Predicate<"Subtarget->hasNontrappingFPToInt()">,
     AssemblerPredicate<"FeatureNontrappingFPToInt", "nontrapping-fptoint">;
@@ -46,18 +50,14 @@ def HasSignExt :
     Predicate<"Subtarget->hasSignExt()">,
     AssemblerPredicate<"FeatureSignExt", "sign-ext">;
 
-def NotHasSignExt :
+def HasTailCall :
-    Predicate<"!Subtarget->hasSignExt()">,
+    Predicate<"Subtarget->hasTailCall()">,
-    AssemblerPredicate<"!FeatureSignExt", "sign-ext">;
+    AssemblerPredicate<"FeatureTailCall", "tail-call">;
 
 def HasExceptionHandling :
     Predicate<"Subtarget->hasExceptionHandling()">,
     AssemblerPredicate<"FeatureExceptionHandling", "exception-handling">;
 
-def NotHasExceptionHandling :
-    Predicate<"!Subtarget->hasExceptionHandling()">,
-    AssemblerPredicate<"!FeatureExceptionHandling", "exception-handling">;
-
 def HasBulkMemory :
     Predicate<"Subtarget->hasBulkMemory()">,
     AssemblerPredicate<"FeatureBulkMemory", "bulk-memory">;

llvm/lib/Target/WebAssembly/WebAssemblySubtarget.h

@@ -44,7 +44,9 @@ class WebAssemblySubtarget final : public WebAssemblyGenSubtargetInfo {
   bool HasSignExt = false;
   bool HasExceptionHandling = false;
   bool HasBulkMemory = false;
+  bool HasMultivalue = false;
   bool HasMutableGlobals = false;
+  bool HasTailCall = false;
 
   /// String name of used CPU.
   std::string CPUString;
@@ -98,7 +100,9 @@ public:
   bool hasSignExt() const { return HasSignExt; }
   bool hasExceptionHandling() const { return HasExceptionHandling; }
   bool hasBulkMemory() const { return HasBulkMemory; }
+  bool hasMultivalue() const { return HasMultivalue; }
   bool hasMutableGlobals() const { return HasMutableGlobals; }
+  bool hasTailCall() const { return HasTailCall; }
 
   /// Parses features string setting specified subtarget options. Definition of
   /// function is auto generated by tblgen.

llvm/test/CodeGen/WebAssembly/multivalue.ll

@@ -0,0 +1,28 @@
+; RUN: llc < %s -asm-verbose=false -verify-machineinstrs -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers -mattr=+multivalue | FileCheck %s
+
+; Test that the multivalue attribute is accepted
+; TODO(tlively): implement multivalue
+
+target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
+target triple = "wasm32-unknown-unknown"
+
+%pair = type { i32, i32 }
+%packed_pair = type <{ i32, i32 }>
+
+; CHECK-LABEL: sret:
+; CHECK-NEXT: sret (i32, i32, i32) -> ()
+define %pair @sret(%pair %p) {
+  ret %pair %p
+}
+
+; CHECK-LABEL: packed_sret:
+; CHECK-NEXT: packed_sret (i32, i32, i32) -> ()
+define %packed_pair @packed_sret(%packed_pair %p) {
+  ret %packed_pair %p
+}
+
+; CHECK-LABEL: .section .custom_section.target_features
+; CHECK-NEXT: .int8 1
+; CHECK-NEXT: .int8 43
+; CHECK-NEXT: .int8 10
+; CHECK-NEXT: .ascii "multivalue"

llvm/test/CodeGen/WebAssembly/tailcall.ll

@@ -0,0 +1,21 @@
+; RUN: llc < %s -asm-verbose=false -verify-machineinstrs -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers -mattr=+tail-call | FileCheck %s
+
+; Test that the tail-call attribute is accepted
+; TODO(tlively): implement tail call
+
+target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
+target triple = "wasm32-unknown-unknown"
+
+; CHECK-LABEL: recursive_tail:
+; CHECK:      i32.call $push[[L0:[0-9]+]]=, recursive_tail{{$}}
+; CHECK-NEXT: return $pop[[L0]]{{$}}
+define i32 @recursive_tail() {
+  %v = tail call i32 @recursive_tail()
+  ret i32 %v
+}
+
+; CHECK-LABEL: .section .custom_section.target_features
+; CHECK-NEXT: .int8 1
+; CHECK-NEXT: .int8 43
+; CHECK-NEXT: .int8 9
+; CHECK-NEXT: .ascii "tail-call"