Remove support for parsing `let` (#4864)

It has been removed from the typed function references proposal, so we no longer
need to support it. Maintaining the test for `let` was difficult because
Binaryen could not emit either text or binary that actually used it.

1 files changed, 0 insertions, 26 deletions

diff --git a/src/wasm-binary.h b/src/wasm-binary.h
index a866881f5..200252da7 100644
--- a/src/wasm-binary.h
+++ b/src/wasm-binary.h
@@ -1085,7 +1085,6 @@ enum ASTNodes {
 
   CallRef = 0x14,
   RetCallRef = 0x15,
-  Let = 0x17,
 
   // gc opcodes
 
@@ -1585,29 +1584,6 @@ public:
 
   std::vector<Expression*> expressionStack;
 
-  // Each let block in the binary adds new locals to the bottom of the index
-  // space. That is, all previously-existing indexes are bumped to higher
-  // indexes. getAbsoluteLocalIndex does this computation.
-  // Note that we must track not just the number of locals added in each let,
-  // but also the absolute index from which they were allocated, as binaryen
-  // will add new locals as it goes for things like stacky code and tuples (so
-  // there isn't a simple way to get to the absolute index from a relative one).
-  // Hence each entry here is a pair of the number of items, and the absolute
-  // index they begin at.
-  struct LetData {
-    // How many items are defined in this let.
-    Index num;
-    // The absolute index from which they are allocated from. That is, if num is
-    // 5 and absoluteStart is 10, then we use indexes 10-14.
-    Index absoluteStart;
-  };
-  std::vector<LetData> letStack;
-
-  // Given a relative index of a local (the one used in the wasm binary), get
-  // the absolute one which takes into account lets, and is the one used in
-  // Binaryen IR.
-  Index getAbsoluteLocalIndex(Index index);
-
   // Control flow structure parsing: these have not just the normal binary
   // data for an instruction, but also some bytes later on like "end" or "else".
   // We must be aware of the connection between those things, for debug info.
@@ -1774,8 +1750,6 @@ public:
   void visitRethrow(Rethrow* curr);
   void visitCallRef(CallRef* curr);
   void visitRefAs(RefAs* curr, uint8_t code);
-  // Let is lowered into a block.
-  void visitLet(Block* curr);
 
   [[noreturn]] void throwError(std::string text);