Pass the target isa when printing a function as a string.

This allows encodings and register names to be printed correctly.

lib/filetests/src/test_dce.rs

@@ -41,7 +41,7 @@ impl SubTest for TestDCE {
             .dce(context.flags_or_isa())
             .map_err(|e| pretty_error(&comp_ctx.func, context.isa, Into::into(e)))?;
 
-        let text = comp_ctx.func.to_string();
+        let text = comp_ctx.func.display(context.isa).to_string();
         run_filecheck(&text, context)
     }
 }

lib/filetests/src/test_licm.rs

@@ -41,7 +41,7 @@ impl SubTest for TestLICM {
             .licm(context.flags_or_isa())
             .map_err(|e| pretty_error(&comp_ctx.func, context.isa, Into::into(e)))?;
 
-        let text = comp_ctx.func.to_string();
+        let text = comp_ctx.func.display(context.isa).to_string();
         run_filecheck(&text, context)
     }
 }

lib/filetests/src/test_postopt.rs

@@ -38,7 +38,7 @@ impl SubTest for TestPostopt {
             .postopt(isa)
             .map_err(|e| pretty_error(&comp_ctx.func, context.isa, Into::into(e)))?;
 
-        let text = comp_ctx.func.to_string();
+        let text = comp_ctx.func.display(isa).to_string();
         run_filecheck(&text, context)
     }
 }

lib/filetests/src/test_preopt.rs

@@ -38,7 +38,7 @@ impl SubTest for TestPreopt {
             .preopt(isa)
             .map_err(|e| pretty_error(&comp_ctx.func, context.isa, Into::into(e)))?;
 
-        let text = &comp_ctx.func.to_string();
+        let text = &comp_ctx.func.display(isa).to_string();
         run_filecheck(&text, context)
     }
 }

lib/filetests/src/test_shrink.rs

@@ -40,7 +40,7 @@ impl SubTest for TestShrink {
             .shrink_instructions(isa)
             .map_err(|e| pretty_error(&comp_ctx.func, context.isa, Into::into(e)))?;
 
-        let text = comp_ctx.func.to_string();
+        let text = comp_ctx.func.display(isa).to_string();
         run_filecheck(&text, context)
     }
 }

lib/filetests/src/test_simple_gvn.rs

@@ -40,7 +40,7 @@ impl SubTest for TestSimpleGVN {
             .simple_gvn(context.flags_or_isa())
             .map_err(|e| pretty_error(&comp_ctx.func, context.isa, Into::into(e)))?;
 
-        let text = comp_ctx.func.to_string();
+        let text = comp_ctx.func.display(context.isa).to_string();
         run_filecheck(&text, context)
     }
 }