Add abort extern

zirgen/Conversions/Typing/BuiltinComponents.cpp

@@ -213,6 +213,7 @@ function Div(lhs: Val, rhs: Val) {
 }
 
 extern Log(message: String, vals: Val...);
+extern Abort();
 extern Assert(x: Val, message: String);
 
 )";

zirgen/Main/RunTests.cpp

@@ -185,6 +185,8 @@ struct TestExternHandler : public zirgen::Zll::ExternHandler {
         valPtrs[i] = &vals[i];
       }
       results = zirgen::Zll::ExternHandler::doExtern("log", message, valPtrs, outCount, failed);
+    } else if (name == "Abort") {
+      *failed = true;
     } else if (name == "Assert") {
       auto condition = args[0]->getBaseFieldVal();
       llvm::StringRef message = args[1]->getAttr<mlir::StringAttr>().getValue();

zirgen/circuit/keccak/src/cpu.rs

@@ -121,6 +121,19 @@ impl<'a> CpuExecContext<'a> {
         tracing::trace!("Read returns {val:?}");
         Ok(val)
     }
+
+    pub fn abort(&self) -> Result<()> {
+        Err(anyhow!("circuit aborted proving"))
+    }
+
+    pub fn assert(&self, condition: Val, message: &str) -> Result<()> {
+        if condition == Val::ZERO {
+            Err(anyhow!(message.to_owned()))
+        } else {
+            Ok(())
+        }
+    }
+
     pub fn log(&self, message: &str, x: impl AsRef<[Val]>) -> Result<()> {
         risc0_zirgen_dsl::codegen::default_log(message, x.as_ref())
     }

zirgen/dsl/test/abort.zir

@@ -0,0 +1,7 @@
+// RUN: not zirgen --test %s 2>&1 | FileCheck %s
+
+test {
+  // CHECK: [0] Abort() -> ()
+  // CHECK-NEXT: error: Evaluation error occured
+  Abort();
+}