Run the verifier in the Context methods when it is enabled.

The test drivers can stop calling comp_ctx.verify because legalize() and
regalloc() do it themselves now.

This also makes it possible for those two passes to return other
CtonError codes in the future, not just verifier errors.

src/filetest/regalloc.rs

@@ -10,7 +10,7 @@ use cretonne::{self, write_function};
 use cton_reader::TestCommand;
 use filetest::subtest::{SubTest, Context, Result, run_filecheck};
 use std::borrow::Cow;
-use utils::pretty_verifier_error;
+use utils::pretty_error;
 
 struct TestRegalloc;
 
@@ -45,10 +45,10 @@ impl SubTest for TestRegalloc {
 
         comp_ctx.flowgraph();
         // TODO: Should we have an option to skip legalization?
-        comp_ctx.legalize(isa);
-        comp_ctx.regalloc(isa);
-        comp_ctx.verify(isa)
-            .map_err(|e| pretty_verifier_error(&comp_ctx.func, e))?;
+        comp_ctx.legalize(isa)
+            .map_err(|e| pretty_error(&comp_ctx.func, e))?;
+        comp_ctx.regalloc(isa)
+            .map_err(|e| pretty_error(&comp_ctx.func, e))?;
 
         let mut text = String::new();
         write_function(&mut text, &comp_ctx.func, Some(isa)).map_err(|e| e.to_string())?;