[lld][WebAssembly] Update comments mentioning legacy function names. NFC

The __wasm_apply_relocs function was split into two separate
functions as part of https://reviews.llvm.org/D93066 but these
comments were not correctly updated at the time.

Differential Revision: https://reviews.llvm.org/D95623

lld/test/wasm/shared.ll

@@ -132,7 +132,7 @@ declare void @func_external()
 ; CHECK-NEXT:           Index:           2
 ; CHECK-NEXT:         Functions:       [ 4, 3 ]
 
-; check the generated code in __wasm_call_ctors and __wasm_apply_relocs functions
+; check the generated code in __wasm_call_ctors and __wasm_apply_data_relocs functions
 ; TODO(sbc): Disassemble and verify instructions.
 
 ; CHECK:        - Type:            CODE

lld/test/wasm/weak-undefined-pic.s

@@ -29,7 +29,7 @@ _start:
 
 # Verify that we do not generate dynamic relocations for the GOT entry.
 
-# CHECK-NOT: __wasm_apply_relocs
+# CHECK-NOT: __wasm_apply_global_relocs
 
 # Verify that we do not generate an import for foo
 
@@ -45,7 +45,7 @@ _start:
 # CHECK-NEXT:           Value:           66560
 # Global 'undefined_weak:foo' representing the GOT entry for foo
 # Unlike other internal GOT entries that need to be mutable this one
-# is immutable and not updated by `__wasm_apply_relocs`
+# is immutable and not updated by `__wasm_apply_global_relocs`
 # CHECK-NEXT:       - Index:           1
 # CHECK-NEXT:         Type:            I32
 # CHECK-NEXT:         Mutable:         false

lld/wasm/MarkLive.cpp

@@ -189,7 +189,7 @@ bool MarkLive::isCallCtorsLive() {
     return false;
 
   // In Emscripten-style PIC, we call `__wasm_call_ctors` which calls
-  // `__wasm_apply_relocs`.
+  // `__wasm_apply_data_relocs`.
   if (config->isPic)
     return true;
 

lld/wasm/SyntheticSections.cpp

@@ -333,7 +333,7 @@ void GlobalSection::writeBody() {
     WasmGlobal global;
     // In the case of dynamic linking, internal GOT entries
     // need to be mutable since they get updated to the correct
-    // runtime value during `__wasm_apply_relocs`.
+    // runtime value during `__wasm_apply_global_relocs`.
     bool mutable_ = config->isPic & !sym->isStub;
     global.Type = {WASM_TYPE_I32, mutable_};
     global.InitExpr.Opcode = WASM_OPCODE_I32_CONST;

lld/wasm/Writer.cpp

@@ -1121,8 +1121,8 @@ void Writer::createStartFunction() {
 
 // For -shared (PIC) output, we create create a synthetic function which will
 // apply any relocations to the data segments on startup.  This function is
-// called __wasm_apply_relocs and is added at the beginning of __wasm_call_ctors
-// before any of the constructors run.
+// called `__wasm_apply_data_relocs` and is added at the beginning of
+// `__wasm_call_ctors` before any of the constructors run.
 void Writer::createApplyDataRelocationsFunction() {
   LLVM_DEBUG(dbgs() << "createApplyDataRelocationsFunction\n");
   // First write the body's contents to a string.
@@ -1160,7 +1160,7 @@ void Writer::createApplyGlobalRelocationsFunction() {
 // in input object.
 void Writer::createCallCtorsFunction() {
   // If __wasm_call_ctors isn't referenced, there aren't any ctors, and we
-  // aren't calling `__wasm_apply_relocs` for Emscripten-style PIC, don't
+  // aren't calling `__wasm_apply_data_relocs` for Emscripten-style PIC, don't
   // define the `__wasm_call_ctors` function.
   if (!WasmSym::callCtors->isLive() && !WasmSym::applyDataRelocs &&
       initFunctions.empty())
@@ -1203,9 +1203,8 @@ void Writer::createCommandExportWrapper(uint32_t functionIndex,
     raw_string_ostream os(bodyContent);
     writeUleb128(os, 0, "num locals");
 
-    // If we have any ctors, or we're calling `__wasm_apply_relocs` for
-    // Emscripten-style PIC, call `__wasm_call_ctors` which performs those
-    // calls.
+    // Call `__wasm_call_ctors` which call static constructors (and
+    // applies any runtime relocations in Emscripten-style PIC mode)
     if (WasmSym::callCtors->isLive()) {
       writeU8(os, WASM_OPCODE_CALL, "CALL");
       writeUleb128(os, WasmSym::callCtors->getFunctionIndex(),