From 8580e9586003b41dfd26b6c15fc49da12dc4cf1e Mon Sep 17 00:00:00 2001
From: Aaron Orenstein <aorenste@meta.com>
Date: Mon, 7 Nov 2022 11:25:20 -0800
Subject: [PATCH] Support for some missing instructions

Summary:
- Exit
- Sub

Reviewed By: edwinsmith

Differential Revision: D41082845

fbshipit-source-id: e33577c411cb01c54513ee89c9d6c910e28d80ca
---
 .../hack/src/hackc/ir/conversions/textual/decls.rs |  2 ++
 hphp/hack/src/hackc/ir/conversions/textual/hack.rs |  2 ++
 .../hackc/ir/conversions/textual/lower/instrs.rs   | 26 +++++++++++++---------
 3 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/hphp/hack/src/hackc/ir/conversions/textual/decls.rs b/hphp/hack/src/hackc/ir/conversions/textual/decls.rs
index 85dec5ee9b2..0692b7d5b72 100644
--- a/hphp/hack/src/hackc/ir/conversions/textual/decls.rs
+++ b/hphp/hack/src/hackc/ir/conversions/textual/decls.rs
@@ -68,6 +68,8 @@ pub fn write_decls(w: &mut dyn std::io::Write) -> Result<()> {
             | Hhbc::Modulo
             | Hhbc::Sub => declare_function(w, &name, &[ty!(mixed), ty!(mixed)], ty!(mixed))?,
 
+            Hhbc::Exit => declare_function(w, &name, &[ty!(mixed)], ty!(noreturn))?,
+
             Hhbc::IsTypeInt | Hhbc::IsTypeNull | Hhbc::IsTypeStr => {
                 declare_function(w, &name, &[ty!(mixed)], ty!(bool))?
             }
diff --git a/hphp/hack/src/hackc/ir/conversions/textual/hack.rs b/hphp/hack/src/hackc/ir/conversions/textual/hack.rs
index e349f450701..c87660bcf62 100644
--- a/hphp/hack/src/hackc/ir/conversions/textual/hack.rs
+++ b/hphp/hack/src/hackc/ir/conversions/textual/hack.rs
@@ -43,6 +43,8 @@ pub(crate) enum Hhbc {
     CmpNeq,
     #[strum(props(Function = "hhbc_cmp_same"))]
     CmpSame,
+    #[strum(props(Function = "hhbc_exit"))]
+    Exit,
     #[strum(props(Function = "hhbc_is_type_int"))]
     IsTypeInt,
     #[strum(props(Function = "hhbc_is_type_null"))]
diff --git a/hphp/hack/src/hackc/ir/conversions/textual/lower/instrs.rs b/hphp/hack/src/hackc/ir/conversions/textual/lower/instrs.rs
index 942c5168eff..088972855c0 100644
--- a/hphp/hack/src/hackc/ir/conversions/textual/lower/instrs.rs
+++ b/hphp/hack/src/hackc/ir/conversions/textual/lower/instrs.rs
@@ -8,6 +8,7 @@ use ir::instr::CmpOp;
 use ir::instr::HasLoc;
 use ir::instr::HasOperands;
 use ir::instr::Hhbc;
+use ir::instr::Terminator;
 use ir::Func;
 use ir::FuncBuilder;
 use ir::FuncBuilderEx as _;
@@ -48,7 +49,7 @@ struct LowerInstrs<'a> {
 }
 
 impl LowerInstrs<'_> {
-    fn handle_with_builtin(&self, builder: &mut FuncBuilder<'_>, instr: &Instr) -> Instr {
+    fn handle_with_builtin(&self, builder: &mut FuncBuilder<'_>, instr: &Instr) -> Option<Instr> {
         let builtin = match instr {
             Instr::Hhbc(Hhbc::CmpOp(_, CmpOp::Eq, _)) => hack::Builtin::Hhbc(hack::Hhbc::CmpEq),
             Instr::Hhbc(Hhbc::CmpOp(_, CmpOp::Gt, _)) => hack::Builtin::Hhbc(hack::Hhbc::CmpGt),
@@ -86,9 +87,10 @@ impl LowerInstrs<'_> {
             Instr::Hhbc(Hhbc::NewObjS(..)) => hack::Builtin::Hhbc(hack::Hhbc::NewObj),
             Instr::Hhbc(Hhbc::Not(..)) => hack::Builtin::Hhbc(hack::Hhbc::Not),
             Instr::Hhbc(Hhbc::Print(..)) => hack::Builtin::Hhbc(hack::Hhbc::Print),
-            _ => unreachable!("Unhandled Instr: {instr:#?}"),
+            Instr::Hhbc(Hhbc::Sub(..)) => hack::Builtin::Hhbc(hack::Hhbc::Sub),
+            _ => return None,
         };
-        builder.hack_builtin(builtin, instr.operands(), instr.loc_id())
+        Some(builder.hack_builtin(builtin, instr.operands(), instr.loc_id()))
     }
 
     fn verify_ret_type_c(&self, builder: &mut FuncBuilder<'_>, vid: ValueId, loc: LocId) -> Instr {
@@ -108,15 +110,12 @@ impl LowerInstrs<'_> {
 
 impl TransformInstr for LowerInstrs<'_> {
     fn apply(&mut self, _iid: InstrId, instr: Instr, builder: &mut FuncBuilder<'_>) -> Instr {
+        if let Some(instr) = self.handle_with_builtin(builder, &instr) {
+            self.changed = true;
+            return instr;
+        }
+
         let instr = match instr {
-            Instr::Hhbc(
-                Hhbc::CmpOp(..)
-                | Hhbc::IsTypeC(..)
-                | Hhbc::Modulo(..)
-                | Hhbc::NewObjS(..)
-                | Hhbc::Not(..)
-                | Hhbc::Print(..),
-            ) => self.handle_with_builtin(builder, &instr),
             Instr::Hhbc(Hhbc::LateBoundCls(loc)) => {
                 if self.method_info.unwrap().is_static {
                     let this = builder.emit(Instr::Hhbc(Hhbc::This(loc)));
@@ -126,6 +125,11 @@ impl TransformInstr for LowerInstrs<'_> {
                     builder.hack_builtin(hack::Builtin::GetStaticClass, &[this], loc)
                 }
             }
+            Instr::Terminator(Terminator::Exit(..)) => {
+                let builtin = hack::Builtin::Hhbc(hack::Hhbc::Exit);
+                builder.emit_hack_builtin(builtin, instr.operands(), instr.loc_id());
+                Instr::unreachable()
+            }
             Instr::Hhbc(Hhbc::VerifyRetTypeC(vid, loc)) => {
                 self.verify_ret_type_c(builder, vid, loc)
             }
-- 
2.11.4.GIT