[DebugInfo] Add debug info to the values emitted in GlobalStructInference (#6709)

Previously the replacement select got the debug info, but we should also copy it
to the values, as often optimizations lead to one of those values remaining by
itself.

Similar to #6652 in general form.

1 files changed, 23 insertions, 15 deletions

diff --git a/src/passes/GlobalStructInference.cpp b/src/passes/GlobalStructInference.cpp
index 0ddbe9b0f..7526cdb76 100644
--- a/src/passes/GlobalStructInference.cpp
+++ b/src/passes/GlobalStructInference.cpp
@@ -50,6 +50,7 @@
 
 #include <variant>
 
+#include "ir/debuginfo.h"
 #include "ir/find_all.h"
 #include "ir/module-utils.h"
 #include "ir/names.h"
@@ -417,29 +418,36 @@ struct GlobalStructInference : public Pass {
         // Helper for optimization: Given a Value, returns what we should read
         // for it.
         auto getReadValue = [&](const Value& value) -> Expression* {
+          Expression* ret;
           if (value.isConstant()) {
             // This is known to be a constant, so simply emit an expression for
             // that constant.
-            return value.getConstant().makeExpression(wasm);
-          }
+            ret = value.getConstant().makeExpression(wasm);
+          } else {
+            // Otherwise, this is non-constant, so we are in the situation where
+            // we want to un-nest the value out of the struct.new it is in. Note
+            // that for later work, as we cannot add a global in parallel.
 
-          // Otherwise, this is non-constant, so we are in the situation where
-          // we want to un-nest the value out of the struct.new it is in. Note
-          // that for later work, as we cannot add a global in parallel.
+            // There can only be one global in a value that is not constant,
+            // which is the global we want to read from.
+            assert(value.globals.size() == 1);
 
-          // There can only be one global in a value that is not constant, which
-          // is the global we want to read from.
-          assert(value.globals.size() == 1);
+            // Create a global.get with temporary name, leaving only the
+            // updating of the name to later work.
+            auto* get = builder.makeGlobalGet(value.globals[0],
+                                              value.getExpression()->type);
 
-          // Create a global.get with temporary name, leaving only the updating
-          // of the name to later work.
-          auto* get = builder.makeGlobalGet(value.globals[0],
-                                            value.getExpression()->type);
+            globalsToUnnest.emplace_back(
+              GlobalToUnnest{value.globals[0], fieldIndex, get});
+
+            ret = get;
+          }
 
-          globalsToUnnest.emplace_back(
-            GlobalToUnnest{value.globals[0], fieldIndex, get});
+          // This value replaces the struct.get, so it should have the same
+          // source location.
+          debuginfo::copyOriginalToReplacement(curr, ret, getFunction());
 
-          return get;
+          return ret;
         };
 
         // We have some globals (at least 2), and so must have at least one