[JITLink] Rename 'i386' namespace and files to 'x86'.

When building on i386, both clang and gcc define a builtin 'i386' macro (see
discussion in llvm/llvm-project#137063). This causes
build errors in the JITLink/i386 backend when attempting to build LLVM on i386.

This commit renames the 'i386' backend (namespaces, APIs and files) to 'x86' to
avoid this issue.

Author: lhames

llvm/include/llvm/ExecutionEngine/JITLink/ELF_i386.h renamed to llvm/include/llvm/ExecutionEngine/JITLink/ELF_x86.h

@@ -1,4 +1,4 @@
-//===--- ELF_i386.h - JIT link functions for ELF/i386 --*- C++ -*----===//
+//===------- ELF_x86.h - JIT link functions for ELF/x86 ------*- C++ -*----===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
@@ -8,33 +8,33 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// jit-link functions for ELF/i386.
+// jit-link functions for ELF/x86.
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_EXECUTIONENGINE_JITLINK_ELF_I386_H
-#define LLVM_EXECUTIONENGINE_JITLINK_ELF_I386_H
+#ifndef LLVM_EXECUTIONENGINE_JITLINK_ELF_X86_H
+#define LLVM_EXECUTIONENGINE_JITLINK_ELF_X86_H
 
 #include "llvm/ExecutionEngine/JITLink/JITLink.h"
 
 namespace llvm {
 namespace jitlink {
 
-/// Create a LinkGraph from an ELF/i386 relocatable object
+/// Create a LinkGraph from an ELF/x86 relocatable object
 ///
 /// Note: The graph does not take ownership of the underlying buffer, nor copy
 /// its contents. The caller is responsible for ensuring that the object buffer
 /// outlives the graph.
 Expected<std::unique_ptr<LinkGraph>>
-createLinkGraphFromELFObject_i386(MemoryBufferRef ObjectBuffer,
-                                  std::shared_ptr<orc::SymbolStringPool> SSP);
+createLinkGraphFromELFObject_x86(MemoryBufferRef ObjectBuffer,
+                                 std::shared_ptr<orc::SymbolStringPool> SSP);
 
-/// jit-link the given object buffer, which must be a ELF i386 relocatable
+/// jit-link the given object buffer, which must be a ELF x86 relocatable
 /// object file.
-void link_ELF_i386(std::unique_ptr<LinkGraph> G,
-                   std::unique_ptr<JITLinkContext> Ctx);
+void link_ELF_x86(std::unique_ptr<LinkGraph> G,
+                  std::unique_ptr<JITLinkContext> Ctx);
 
 } // end namespace jitlink
 } // end namespace llvm
 
-#endif // LLVM_EXECUTIONENGINE_JITLINK_ELF_I386_H
+#endif // LLVM_EXECUTIONENGINE_JITLINK_ELF_X86_H

llvm/include/llvm/ExecutionEngine/JITLink/i386.h renamed to llvm/include/llvm/ExecutionEngine/JITLink/x86.h

@@ -1,24 +1,25 @@
-//=== i386.h - Generic JITLink i386 edge kinds, utilities -*- C++ -*-===//
+//===----- x86.h - Generic JITLink x86 edge kinds, utilities ----*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
-// Generic utilities for graphs representing i386 objects.
+// Generic utilities for graphs representing x86 objects.
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_EXECUTIONENGINE_JITLINK_I386_H
-#define LLVM_EXECUTIONENGINE_JITLINK_I386_H
+#ifndef LLVM_EXECUTIONENGINE_JITLINK_X86_H
+#define LLVM_EXECUTIONENGINE_JITLINK_X86_H
 
 #include "llvm/ExecutionEngine/JITLink/JITLink.h"
 #include "llvm/ExecutionEngine/JITLink/TableManager.h"
 
-namespace llvm::jitlink::i386 {
-/// Represets i386 fixups
-enum EdgeKind_i386 : Edge::Kind {
+namespace llvm::jitlink::x86 {
+
+/// Represets x86 fixups
+enum EdgeKind_x86 : Edge::Kind {
 
   /// A plain 32-bit pointer value relocation.
   ///
@@ -174,7 +175,7 @@ enum EdgeKind_i386 : Edge::Kind {
   BranchPCRel32ToPtrJumpStubBypassable,
 };
 
-/// Returns a string name for the given i386 edge. For debugging purposes
+/// Returns a string name for the given x86 edge. For debugging purposes
 /// only
 const char *getEdgeKindName(Edge::Kind K);
 
@@ -249,13 +250,13 @@ inline Error applyFixup(LinkGraph &G, Block &B, const Edge &E,
   return Error::success();
 }
 
-/// i386 pointer size.
+/// x86 pointer size.
 constexpr uint32_t PointerSize = 4;
 
-/// i386 null pointer content.
+/// x86 null pointer content.
 extern const char NullPointerContent[PointerSize];
 
-/// i386 pointer jump stub content.
+/// x86 pointer jump stub content.
 ///
 /// Contains the instruction sequence for an indirect jump via an in-memory
 /// pointer:
@@ -406,6 +407,6 @@ class PLTTableManager : public TableManager<PLTTableManager> {
 /// target
 Error optimizeGOTAndStubAccesses(LinkGraph &G);
 
-} // namespace llvm::jitlink::i386
+} // namespace llvm::jitlink::x86
 
-#endif // LLVM_EXECUTIONENGINE_JITLINK_I386_H
+#endif // LLVM_EXECUTIONENGINE_JITLINK_X86_H

llvm/lib/ExecutionEngine/JITLink/CMakeLists.txt

@@ -23,10 +23,10 @@ add_llvm_component_library(LLVMJITLink
   ELFLinkGraphBuilder.cpp
   ELF_aarch32.cpp
   ELF_aarch64.cpp
-  ELF_i386.cpp
   ELF_loongarch.cpp
   ELF_ppc64.cpp
   ELF_riscv.cpp
+  ELF_x86.cpp
   ELF_x86_64.cpp
 
   # COFF
@@ -43,10 +43,10 @@ add_llvm_component_library(LLVMJITLink
   # Architectures:
   aarch32.cpp
   aarch64.cpp
-  i386.cpp
   loongarch.cpp
   ppc64.cpp
   riscv.cpp
+  x86.cpp
   x86_64.cpp
 
   ADDITIONAL_HEADER_DIRS

llvm/lib/ExecutionEngine/JITLink/ELF.cpp

@@ -15,10 +15,10 @@
 #include "llvm/BinaryFormat/ELF.h"
 #include "llvm/ExecutionEngine/JITLink/ELF_aarch32.h"
 #include "llvm/ExecutionEngine/JITLink/ELF_aarch64.h"
-#include "llvm/ExecutionEngine/JITLink/ELF_i386.h"
 #include "llvm/ExecutionEngine/JITLink/ELF_loongarch.h"
 #include "llvm/ExecutionEngine/JITLink/ELF_ppc64.h"
 #include "llvm/ExecutionEngine/JITLink/ELF_riscv.h"
+#include "llvm/ExecutionEngine/JITLink/ELF_x86.h"
 #include "llvm/ExecutionEngine/JITLink/ELF_x86_64.h"
 #include "llvm/Object/ELF.h"
 #include <cstring>
@@ -101,7 +101,7 @@ createLinkGraphFromELFObject(MemoryBufferRef ObjectBuffer,
   case ELF::EM_X86_64:
     return createLinkGraphFromELFObject_x86_64(ObjectBuffer, std::move(SSP));
   case ELF::EM_386:
-    return createLinkGraphFromELFObject_i386(ObjectBuffer, std::move(SSP));
+    return createLinkGraphFromELFObject_x86(ObjectBuffer, std::move(SSP));
   default:
     return make_error<JITLinkError>(
         "Unsupported target machine architecture in ELF object " +
@@ -139,7 +139,7 @@ void link_ELF(std::unique_ptr<LinkGraph> G,
     link_ELF_x86_64(std::move(G), std::move(Ctx));
     return;
   case Triple::x86:
-    link_ELF_i386(std::move(G), std::move(Ctx));
+    link_ELF_x86(std::move(G), std::move(Ctx));
     return;
   default:
     Ctx->notifyFailed(make_error<JITLinkError>(