From 8f2004d360dde108f90d2b49b0609bd43b7b6d7d Mon Sep 17 00:00:00 2001 From: Vincent Ambo Date: Wed, 21 Sep 2022 00:32:49 +0300 Subject: refactor(tvix/eval): add VM::call_value helper method This makes it possible to call a callable value (builtin or closure/lambda) directly, without unwrapping it first. This is needed for pretty much all higher-order functions to work correctly. This is mostly equivalent to the previous code in coerce_to_string for calling `__toString`, except it expects the argument(s) to already be placed on the stack. Note that the span for the `NotCallable` error is not currently guaranteed to make any sense, will experiment with this. Change-Id: I821224368d438a28900858b343defc1817e46a0a Reviewed-on: https://cl.tvl.fyi/c/depot/+/6717 Tested-by: BuildkiteCI Reviewed-by: sterni --- tvix/eval/src/vm.rs | 35 +++++++++++++++++++++++------------ 1 file changed, 23 insertions(+), 12 deletions(-) (limited to 'tvix/eval/src/vm.rs') diff --git a/tvix/eval/src/vm.rs b/tvix/eval/src/vm.rs index 909e219bcd..69ffc7d5c2 100644 --- a/tvix/eval/src/vm.rs +++ b/tvix/eval/src/vm.rs @@ -175,7 +175,28 @@ impl<'o> VM<'o> { } } - #[allow(clippy::let_and_return)] // due to disassembler + /// Execute the given value in this VM's context, if it is a + /// callable. + /// + /// The stack of the VM must be prepared with all required + /// arguments before calling this and the value must have already + /// been forced. + pub fn call_value(&mut self, callable: &Value) -> EvalResult { + match callable { + Value::Closure(c) => self.call(c.lambda(), c.upvalues().clone(), 1), + + Value::Builtin(b) => { + self.call_builtin(b.clone())?; + Ok(self.pop()) + } + + Value::Thunk(t) => self.call_value(&t.value()), + + // TODO: this isn't guaranteed to be a useful span, actually + _ => Err(self.error(ErrorKind::NotCallable)), + } + } + /// Execute the given lambda in this VM's context, returning its /// value after its stack frame completes. pub fn call( @@ -456,17 +477,7 @@ impl<'o> VM<'o> { OpCode::OpCall => { let callable = self.pop(); - match callable { - Value::Closure(closure) => { - let result = - self.call(closure.lambda(), closure.upvalues().clone(), 1)?; - self.push(result) - } - - Value::Builtin(builtin) => self.call_builtin(builtin)?, - - _ => return Err(self.error(ErrorKind::NotCallable)), - }; + self.call_value(&callable)?; } OpCode::OpTailCall => { -- cgit 1.4.1