From f90d9a74bd9649d8e0b81d860dbaa3d6a7ca7ecb Mon Sep 17 00:00:00 2001
From: Brian Carroll <brian.carroll.ireland@gmail.com>
Date: Wed, 29 Dec 2021 21:08:16 +0000
Subject: [PATCH] Do not inline builtin wrapper for Str.toNum

---
 compiler/gen_wasm/src/low_level.rs | 29 ++++++++++++++---------------
 compiler/module/src/low_level.rs   | 28 ++++++++++++++--------------
 2 files changed, 28 insertions(+), 29 deletions(-)

diff --git a/compiler/gen_wasm/src/low_level.rs b/compiler/gen_wasm/src/low_level.rs
index 93c22bfd27..b7ba2beeb4 100644
--- a/compiler/gen_wasm/src/low_level.rs
+++ b/compiler/gen_wasm/src/low_level.rs
@@ -49,22 +49,21 @@ pub fn dispatch_low_level<'a>(
         }
         StrCountGraphemes => return BuiltinCall(bitcode::STR_COUNT_GRAPEHEME_CLUSTERS),
         StrToNum => {
-            if let Layout::Union(UnionLayout::NonRecursive(union_layout)) = mono_layout {
-                // match on the return layout to figure out which zig builtin we need
-                let intrinsic = match union_layout[1][0] {
-                    Layout::Builtin(Builtin::Int(int_width)) => &bitcode::STR_TO_INT[int_width],
-                    Layout::Builtin(Builtin::Float(float_width)) => {
-                        &bitcode::STR_TO_FLOAT[float_width]
-                    }
-                    Layout::Builtin(Builtin::Decimal) => bitcode::DEC_FROM_STR,
-                    rest => internal_error!("Unexpected builtin {:?} for StrToNum", rest),
-                };
+            let number_layout = match mono_layout {
+                Layout::Union(UnionLayout::NonRecursive(tags)) => tags[1][0],
+                Layout::Struct(fields) => fields[0], // TODO: why is it sometimes a struct?
+                _ => internal_error!("Unexpected mono layout {:?} for StrToNum", mono_layout),
+            };
+            // match on the return layout to figure out which zig builtin we need
+            let intrinsic = match number_layout {
+                Layout::Builtin(Builtin::Int(int_width)) => &bitcode::STR_TO_INT[int_width],
+                Layout::Builtin(Builtin::Float(float_width)) => &bitcode::STR_TO_FLOAT[float_width],
+                Layout::Builtin(Builtin::Decimal) => bitcode::DEC_FROM_STR,
+                rest => internal_error!("Unexpected builtin {:?} for StrToNum", rest),
+            };
 
-                return BuiltinCall(intrinsic);
-            } else {
-                internal_error!("Unexpected mono layout {:?} for StrToNum", mono_layout);
-            }
-        } // choose builtin based on storage size
+            return BuiltinCall(intrinsic);
+        }
         StrFromInt => {
             // This does not get exposed in user space. We switched to NumToStr instead.
             // We can probably just leave this as NotImplemented. We may want remove this LowLevel.
diff --git a/compiler/module/src/low_level.rs b/compiler/module/src/low_level.rs
index 1673c55d3d..7c2607cffb 100644
--- a/compiler/module/src/low_level.rs
+++ b/compiler/module/src/low_level.rs
@@ -198,20 +198,20 @@ impl LowLevel {
             Symbol::STR_TRIM => Some(StrTrim),
             Symbol::STR_TRIM_LEFT => Some(StrTrimLeft),
             Symbol::STR_TRIM_RIGHT => Some(StrTrimRight),
-            Symbol::STR_TO_DEC => Some(StrToNum),
-            Symbol::STR_TO_F64 => Some(StrToNum),
-            Symbol::STR_TO_F32 => Some(StrToNum),
-            Symbol::STR_TO_NAT => Some(StrToNum),
-            Symbol::STR_TO_U128 => Some(StrToNum),
-            Symbol::STR_TO_I128 => Some(StrToNum),
-            Symbol::STR_TO_U64 => Some(StrToNum),
-            Symbol::STR_TO_I64 => Some(StrToNum),
-            Symbol::STR_TO_U32 => Some(StrToNum),
-            Symbol::STR_TO_I32 => Some(StrToNum),
-            Symbol::STR_TO_U16 => Some(StrToNum),
-            Symbol::STR_TO_I16 => Some(StrToNum),
-            Symbol::STR_TO_U8 => Some(StrToNum),
-            Symbol::STR_TO_I8 => Some(StrToNum),
+            Symbol::STR_TO_DEC => None,
+            Symbol::STR_TO_F64 => None,
+            Symbol::STR_TO_F32 => None,
+            Symbol::STR_TO_NAT => None,
+            Symbol::STR_TO_U128 => None,
+            Symbol::STR_TO_I128 => None,
+            Symbol::STR_TO_U64 => None,
+            Symbol::STR_TO_I64 => None,
+            Symbol::STR_TO_U32 => None,
+            Symbol::STR_TO_I32 => None,
+            Symbol::STR_TO_U16 => None,
+            Symbol::STR_TO_I16 => None,
+            Symbol::STR_TO_U8 => None,
+            Symbol::STR_TO_I8 => None,
             Symbol::LIST_LEN => Some(ListLen),
             Symbol::LIST_GET => None,
             Symbol::LIST_SET => None,