Merge branch 'master' into virtual_function_calls

JuliaHubOSS · Jan 13, 2024 · 8c4c719 · 8c4c719
2 parents cba313d + 1bc2950
commit 8c4c719
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Showing 3 changed files with 15 additions and 1 deletion.
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
@@ -65,7 +65,7 @@ jobs:
       - name: Build
         run: |
           mkdir build
-          cmake -S . -B build -DLLVM_INCLUDE_TESTS=On
+          cmake -S . -B build -DLLVM_INCLUDE_TESTS=On -DLLVM_DIR=/usr/lib/llvm-16/cmake
           cmake --build build
 
       - name: Test

diff --git a/lib/Target/CBackend/CBackend.cpp b/lib/Target/CBackend/CBackend.cpp
@@ -2573,6 +2573,7 @@ void CWriter::generateHeader(Module &M) {
       case Intrinsic::trunc:
       case Intrinsic::umax:
       case Intrinsic::umin:
+      case Intrinsic::is_constant:
         intrinsicsToDefine.push_back(&*I);
         continue;
       }
@@ -4654,6 +4655,9 @@ void CWriter::printIntrinsicDefinition(FunctionType *funT, unsigned Opcode,
     case Intrinsic::umin:
       Out << "  r = a < b ? a : b;\n";
       break;
+    case Intrinsic::is_constant:
+      Out << "  r = 0 /* llvm.is.constant */;\n";
+      break;
     }
 
   } else {
@@ -4775,6 +4779,7 @@ bool CWriter::lowerIntrinsics(Function &F) {
           case Intrinsic::dbg_declare:
           case Intrinsic::umax:
           case Intrinsic::umin:
+          case Intrinsic::is_constant:
             // We directly implement these intrinsics
             break;
 
@@ -5089,6 +5094,7 @@ bool CWriter::visitBuiltinCall(CallInst &I, Intrinsic::ID ID) {
   case Intrinsic::trap:
   case Intrinsic::umax:
   case Intrinsic::umin:
+  case Intrinsic::is_constant:
     return false; // these use the normal function call emission
   }
 }

diff --git a/test/cpp_tests/test_is_constant.cpp b/test/cpp_tests/test_is_constant.cpp
@@ -0,0 +1,8 @@
+int f(int i) {
+  if (__builtin_constant_p(i) &&
+      i == 1) /* generates the llvm.is.constant.i32 intrinsic at -O0 */
+    return i + 5;
+  return 6;
+}
+
+int main() { return f(1); }