Rebase onto llvmorg-18.1.6

.github/workflows/widberg-build.yml

@@ -0,0 +1,23 @@
+name: Widberg Build
+
+on: [push, pull_request]
+
+jobs:
+ build:
+ name: Build
+ runs-on: windows-latest
+ steps:
+ - name: Checkout
+ uses: actions/checkout@v3
+
+ - uses: ilammy/[email protected]
+ - name: Build
+ run: |
+ cmake -S llvm -B build -G Ninja -DCMAKE_BUILD_TYPE=RelWithDebInfo -DLLVM_ENABLE_PROJECTS="clang" -DLLVM_ENABLE_ASSERTIONS=ON -DLLVM_TARGETS_TO_BUILD="X86"
+ cmake --build build --config RelWithDebInfo --target clang
+
+ - name: Archive Artifacts
+ uses: actions/upload-artifact@v3
+ with:
+ name: widberg-windows-x86_64-${{ github.sha }}
+ path: ./build/bin/clang-cl.exe

.github/workflows/widberg-release.yml

@@ -0,0 +1,46 @@
+name: Widberg Release
+
+on:
+ push:
+ tags:
+ - 'widberg-*'
+
+jobs:
+ build:
+ name: Publish
+ runs-on: windows-latest
+ steps:
+ - name: Checkout
+ uses: actions/checkout@v3
+
+ - uses: ilammy/[email protected]
+ - name: Build
+ run: |
+ cmake -S llvm -B build -G Ninja -DCMAKE_BUILD_TYPE=RelWithDebInfo -DLLVM_ENABLE_PROJECTS="clang" -DLLVM_ENABLE_ASSERTIONS=ON -DLLVM_TARGETS_TO_BUILD="X86"
+ cmake --build build --config RelWithDebInfo --target clang
+
+ - name: Package
+ run: |
+ cd build/bin/
+ 7z a ../../bin.zip clang-cl.exe
+ 
+ - name: Create Release
+ id: create_release
+ uses: actions/create-release@v1
+ env:
+ GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+ with:
+ tag_name: ${{ github.ref }}
+ release_name: Release ${{ github.ref }}
+ draft: false
+ prerelease: false
+
+ - name: Upload Archive to Release
+ uses: actions/upload-release-asset@v1
+ env:
+ GITHUB_TOKEN: ${{ github.token }}
+ with:
+ upload_url: ${{ steps.create_release.outputs.upload_url }}
+ asset_name: ${{ github.ref_name }}-windows-x86_64-${{ github.sha }}.zip
+ asset_path: bin.zip
+ asset_content_type: application/zip

README.md

@@ -1,3 +1,144 @@
+# The LLVM Compiler Infrastructure With Widberg Extensions
+
+The LLVM Compiler Infrastructure With Widberg Extensions, affectionately called
+the Widpiler, is a fork of LLVM (17.0.5) intended to implement C/C++ language
+features in LLVM/Clang to aid in reverse engineering. Currently, the
+scope of this project covers a subset of the IDA Pro [__usercall
+syntax](wiki/User‐Defined-Calling-Conventions) and [shifted pointers](wiki/Shifted-Pointers). This is a research project and not production ready.
+
+[![Build Status](https://github.com/widberg/llvm-project-widberg-extensions/actions/workflows/widberg-build.yml/badge.svg?branch=main)](https://github.com/widberg/llvm-project-widberg-extensions/actions/workflows/widberg-build.yml)
+[![GitHub release (latest SemVer)](https://img.shields.io/github/v/release/widberg/llvm-project-widberg-extensions)](https://github.com/widberg/llvm-project-widberg-extensions/releases)
+[![Release Nightly](https://img.shields.io/badge/release-nightly-5e025f?labelColor=301934)](https://nightly.link/widberg/llvm-project-widberg-extensions/workflows/widberg-build/main)
+
+## Example
+
+An example of the syntax that is currently supported is as follows:
+
+```cpp
+// __usercall
+// https://www.hex-rays.com/products/ida/support/idadoc/1361.shtml
+long long __usercall __spoils<eax,esi>
+square@<ebx:ecx>(long long num@<eax:edx>) {
+ return num * num;
+}
+
+bool __usercall is_even@<al>(int num) {
+ return num % 2 == 0;
+}
+
+void __userpurge is_odd(int num, bool &result@<eax>) {
+ result = num % 2 == 1;
+}
+
+auto is_odd_also = is_odd;
+
+int *__usercall call_fn_ptr@<ebx>(int *(__usercall *x)@<eax>(long @<ecx>)@<edx>) {
+ return x(1337);
+}
+
+// __shifted
+// https://hex-rays.com/products/ida/support/idadoc/1695.shtml
+typedef struct vec3f {
+ float x;
+ float y;
+ float z;
+} vec3f_t;
+
+typedef struct player {
+ char name[16];
+ int health;
+ int armor;
+ int ammo;
+ vec3f_t pos;
+} player_t;
+
+const char *get_player_name_from_shifted_pos_pointer(const vec3f_t *__shifted(player_t, 0x1C) pos) {
+ return ADJ(pos)->name;
+}
+```
+
+The first thing most people coming from MSVC say to me when I tell them
+about this project is, "I won't have to do the __fastcall/__thiscall trick
+anymore." What they don't know is that Clang already allows __thiscall on
+non-member functions without this fork. For example the following is
+acceptable in mainline Clang as well as this fork and produces the correct
+output (_this in ecx, other args on the stack):
+
+```cpp
+int __thiscall square(void *_this, int num) {
+ return num * num;
+}
+```
+
+## Compiler Explorer
+
+The compiler is available on the [Compiler Explorer website](https://godbolt.org/z/j4dPsE8rq).
+
+## Motivation
+
+The goal of the project is not to recompile decomplied code in all cases, but rather to provide a familiar syntax for common patterns and reduce the amount of inline assembly and fiddling required when writing high-level patch code. However, by providing this syntax it is possible to recompile decompiled code in some cases. With the addition of [defs.h](#defs.h) most individual functions can be recompiled with little to no modification. Recompiling an entire binary will still require great effort, but is made easier by this project.
+
+## Status
+
+The project is semi-functional but lacks polish. Correct syntax will be accepted
+and generate correct code in most cases; however, incorrect syntax is handled
+largely by asserts and internal compiler errors, especially in X86_64. More work
+needs to be done to take advantage of Clang's diagnostics infrastructure and
+produce pretty errors rather than compiler stack traces. Additionally, some
+incorrect syntax is accepted and ignored rather than reported. Currently, only
+the X86_32 and X86_64 backends are supported.
+
+Next steps are to improve the diagnostics reporting as described above and fix
+the bugs. Pull requests and issues are encouraged; especially pull requests
+adding tests.
+
+## Enable and Disable the Extensions
+
+By default, the extensions are enabled. They can be disabled using the
+Clang option `-fno-widberg-extensions`.
+
+## Verify Widberg Extensions Are Present
+
+The following construct can be used in source files to verify that the
+widberg extensions are present:
+
+```cpp
+#ifndef __has_feature
+# define __has_feature(x) 0 // Compatibility with non-clang compilers.
+#endif
+#ifndef __has_extension
+# define __has_extension __has_feature // Compatibility with pre-3.0 compilers.
+#endif
+
+#if !__has_extension(widberg)
+# error "This file requires a compiler that implements the widberg extensions."
+#endif
+```
+
+Also, the preprocessor macro `__widberg__` is predefined if the extensions are present.
+
+## defs.h
+
+An alternative implementation of defs.h from the Hex-Rays decompiler sdk intended to be used with this project can be found at https://github.com/widberg/widberg-defs. A lot of the stuff in there is overkill for writing patch code, but it is useful for recompiling decompiled code.
+
+## Build
+
+Use `x64 Native Tools Command Prompt`
+
+```sh
+cmake -S llvm -B build -G Ninja -DCMAKE_BUILD_TYPE=RelWithDebInfo -DLLVM_ENABLE_PROJECTS="clang" -DLLVM_ENABLE_ASSERTIONS=ON -DLLVM_TARGETS_TO_BUILD="X86"
+cmake --build build --config RelWithDebInfo --target clang
+```
+
+# Affiliation with LLVM (Or Lack Thereof)
+
+This project is not affiliated with the LLVM project in any way.
+This project, like the LLVM project, is under the Apache License
+v2.0 with LLVM Exceptions. I have no intention of upstreaming any
+of the changes made in this repository as I believe they are not
+useful to most people. The original LLVM project README.md begins
+below.
+
 # The LLVM Compiler Infrastructure
 
 [![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/llvm/llvm-project/badge)](https://securityscorecards.dev/viewer/?uri=github.com/llvm/llvm-project)

clang/include/clang-c/Index.h

@@ -2952,7 +2952,8 @@ enum CXTypeKind {
 
  CXType_ExtVector = 176,
  CXType_Atomic = 177,
- CXType_BTFTagAttributed = 178
+ CXType_BTFTagAttributed = 178,
+ CXType_Shifted = 179,
 };
 
 /**
@@ -2982,6 +2983,9 @@ enum CXCallingConv {
  CXCallingConv_AArch64SVEPCS = 18,
  CXCallingConv_M68kRTD = 19,
 
+ CXCallingConv_UserCall = 98,
+ CXCallingConv_UserPurge = 99,
+
  CXCallingConv_Invalid = 100,
  CXCallingConv_Unexposed = 200
 };

clang/include/clang/AST/ASTContext.h

@@ -246,6 +246,7 @@ class ASTContext : public RefCountedBase<ASTContext> {
  mutable llvm::ContextualFoldingSet<DependentBitIntType, ASTContext &>
  DependentBitIntTypes;
  llvm::FoldingSet<BTFTagAttributedType> BTFTagAttributedTypes;
+ llvm::FoldingSet<ShiftedType> ShiftedTypes;
 
  mutable llvm::FoldingSet<QualifiedTemplateName> QualifiedTemplateNames;
  mutable llvm::FoldingSet<DependentTemplateName> DependentTemplateNames;
@@ -1606,6 +1607,9 @@ class ASTContext : public RefCountedBase<ASTContext> {
  QualType getBTFTagAttributedType(const BTFTypeTagAttr *BTFAttr,
  QualType Wrapped);
 
+ QualType getShiftedType(const ShiftedAttr *SAttr,
+ QualType Wrapped);
+
  QualType
  getSubstTemplateTypeParmType(QualType Replacement, Decl *AssociatedDecl,
  unsigned Index,

clang/include/clang/AST/ASTNodeTraverser.h

@@ -396,6 +396,9 @@ class ASTNodeTraverser
  void VisitBTFTagAttributedType(const BTFTagAttributedType *T) {
  Visit(T->getWrappedType());
  }
+ void VisitShiftedType(const ShiftedType *T) {
+ Visit(T->getWrappedType());
+ }
  void VisitSubstTemplateTypeParmType(const SubstTemplateTypeParmType *) {}
  void
  VisitSubstTemplateTypeParmPackType(const SubstTemplateTypeParmPackType *T) {

clang/include/clang/AST/DeclBase.h

@@ -63,6 +63,7 @@ class Stmt;
 class StoredDeclsMap;
 class TemplateDecl;
 class TemplateParameterList;
+class WidbergLocation;
 class TranslationUnitDecl;
 class UsingDirectiveDecl;
 
@@ -284,6 +285,9 @@ class alignas(8) Decl {
  /// Loc - The location of this decl.
  SourceLocation Loc;
 
+ WidbergLocation *WidLoc = nullptr;
+ WidbergLocation *WidRetLoc = nullptr;
+
  /// DeclKind - This indicates which class this is.
  LLVM_PREFERRED_TYPE(Kind)
  unsigned DeclKind : 7;
@@ -393,7 +397,7 @@ class alignas(8) Decl {
 protected:
  Decl(Kind DK, DeclContext *DC, SourceLocation L)
  : NextInContextAndBits(nullptr, getModuleOwnershipKindForChildOf(DC)),
- DeclCtx(DC), Loc(L), DeclKind(DK), InvalidDecl(false), HasAttrs(false),
+ DeclCtx(DC), Loc(L), WidLoc(nullptr), WidRetLoc(nullptr), DeclKind(DK), InvalidDecl(false), HasAttrs(false),
  Implicit(false), Used(false), Referenced(false),
  TopLevelDeclInObjCContainer(false), Access(AS_none), FromASTFile(0),
  IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
@@ -402,7 +406,7 @@ class alignas(8) Decl {
  }
 
  Decl(Kind DK, EmptyShell Empty)
- : DeclKind(DK), InvalidDecl(false), HasAttrs(false), Implicit(false),
+ : WidLoc(nullptr), WidRetLoc(nullptr), DeclKind(DK), InvalidDecl(false), HasAttrs(false), Implicit(false),
  Used(false), Referenced(false), TopLevelDeclInObjCContainer(false),
  Access(AS_none), FromASTFile(0),
  IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
@@ -444,6 +448,12 @@ class alignas(8) Decl {
  SourceLocation getLocation() const { return Loc; }
  void setLocation(SourceLocation L) { Loc = L; }
 
+ WidbergLocation *getWidbergLocation() const { return WidLoc; };
+ void setWidbergLocation(WidbergLocation *WL) { WidLoc = WL; };
+
+ WidbergLocation *getWidbergReturnLocation() const { return WidRetLoc; };
+ void setWidbergReturnLocation(WidbergLocation *WL) { WidRetLoc = WL; };
+
  Kind getKind() const { return static_cast<Kind>(DeclKind); }
  const char *getDeclKindName() const;