refactor(compiler): rename force_out_of_gas to single_error

The setting collapses every failure path to a single OutOfGas
constant; "single_error" reflects what it does (one merged error
result) rather than the implementation detail of which result code
is used as the placeholder.

Author: DaniPopes

crates/revmc-cli/src/cmd/run.rs

@@ -79,9 +79,9 @@ pub(crate) struct RunArgs {
     no_gas: bool,
     #[arg(long)]
     no_len_checks: bool,
-    /// Force all return paths to yield `OutOfGas`.
+    /// Force all failure paths to yield a single `OutOfGas`.
     #[arg(long)]
-    force_out_of_gas: bool,
+    single_error: bool,
     /// Inspect the stack after the function has been executed.
     #[arg(long)]
     inspect_stack: bool,
@@ -157,8 +157,8 @@ impl RunArgs {
             compiler.gas_metering(!self.no_gas);
             unsafe { compiler.stack_bound_checks(!self.no_len_checks) };
             compiler.debug_assertions(self.debug_assertions);
-            if self.force_out_of_gas {
-                compiler.force_out_of_gas(true);
+            if self.single_error {
+                compiler.single_error(true);
             }
 
             compiler.set_module_name(name);

crates/revmc-codegen/src/compiler/mod.rs

@@ -425,8 +425,8 @@ impl<B: Backend> EvmCompiler<B> {
     /// Useful for benchmarking the cost of failure-result materialization.
     ///
     /// Defaults to `false`.
-    pub fn force_out_of_gas(&mut self, yes: bool) {
-        self.config.force_out_of_gas = yes;
+    pub fn single_error(&mut self, yes: bool) {
+        self.config.single_error = yes;
     }
 
     /// Sets custom gas parameters.

crates/revmc-codegen/src/compiler/translate/mod.rs

@@ -31,7 +31,7 @@ pub(super) struct FcxConfig {
     pub(super) inspect_stack: bool,
     pub(super) stack_bound_checks: bool,
     pub(super) gas_metering: bool,
-    pub(super) force_out_of_gas: bool,
+    pub(super) single_error: bool,
 }
 
 impl Default for FcxConfig {
@@ -44,7 +44,7 @@ impl Default for FcxConfig {
             inspect_stack: false,
             stack_bound_checks: true,
             gas_metering: true,
-            force_out_of_gas: true,
+            single_error: true,
         }
     }
 }
@@ -439,10 +439,10 @@ impl<'a, B: Backend> FunctionCx<'a, B> {
         // Finalize the failure block.
         fx.bcx.switch_to_block(fx.failure_block.unwrap());
         if !fx.incoming_failures.is_empty() {
-            // `force_out_of_gas` collapses every error path to a generic OOG; this is
+            // `single_error` collapses every error path to a generic OOG; this is
             // safe because failures are semantically interchangeable for callers that
             // only branch on success vs failure.
-            let failure_value = if config.force_out_of_gas {
+            let failure_value = if config.single_error {
                 fx.bcx.iconst(fx.i8_type, InstructionResult::OutOfGas as i64)
             } else {
                 fx.bcx.phi(fx.i8_type, &fx.incoming_failures)