[lld] [LLD] Add support for statically resolved vendor-specific RISCV relocations. (PR #169273)

[Sam Elliott via llvm-commits]

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@@ -0,0 +1,113 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLD_ELF_ARCH_RISCVINTERNALRELOCATIONS_H
+#define LLD_ELF_ARCH_RISCVINTERNALRELOCATIONS_H
+
+#include "Relocations.h"
+#include "Symbols.h"
+
+namespace lld::elf {
+
+// Bit 8 of RelType is used to indicate linker-internal relocations that are
+// not vendor-specific.
+// These are internal relocation numbers for GP/X0 relaxation. They aren't part
+// of the psABI spec.
+constexpr uint32_t INTERNAL_R_RISCV_GPREL_I = 256;
+constexpr uint32_t INTERNAL_R_RISCV_GPREL_S = 257;
+constexpr uint32_t INTERNAL_R_RISCV_X0REL_I = 258;
+constexpr uint32_t INTERNAL_R_RISCV_X0REL_S = 259;
+
+// Bits 9 -> 31 of RelType are used to indicate vendor-specific relocations.
+constexpr uint32_t INTERNAL_RISCV_VENDOR_MASK = 0xFFFFFFFF << 9;
+constexpr uint32_t INTERNAL_RISCV_VENDOR_QUALCOMM = 1 << 9;
+constexpr uint32_t INTERNAL_RISCV_VENDOR_ANDES = 2 << 9;
+
+constexpr uint32_t INTERNAL_RISCV_QC_ABS20_U =
+    INTERNAL_RISCV_VENDOR_QUALCOMM | llvm::ELF::R_RISCV_QC_ABS20_U;
+constexpr uint32_t INTERNAL_RISCV_QC_E_BRANCH =
+    INTERNAL_RISCV_VENDOR_QUALCOMM | llvm::ELF::R_RISCV_QC_E_BRANCH;
+constexpr uint32_t INTERNAL_RISCV_QC_E_32 =
+    INTERNAL_RISCV_VENDOR_QUALCOMM | llvm::ELF::R_RISCV_QC_E_32;
+constexpr uint32_t INTERNAL_RISCV_QC_E_CALL_PLT =
+    INTERNAL_RISCV_VENDOR_QUALCOMM | llvm::ELF::R_RISCV_QC_E_CALL_PLT;
+
+constexpr uint32_t INTERNAL_RISCV_NDS_BRANCH_10 =
+    INTERNAL_RISCV_VENDOR_ANDES | llvm::ELF::R_RISCV_NDS_BRANCH_10;
+
+uint32_t getRISCVVendorRelMarker(llvm::StringRef rvVendor);
+std::optional<llvm::StringRef> getRISCVVendorString(RelType ty);
+
+class vendor_reloc_iterator {
+public:
+  using iterator_category = std::forward_iterator_tag;
+  using value_type = Relocation;
+  using difference_type = std::ptrdiff_t;
+  using pointer = Relocation *;
+  using reference = Relocation; // returned by value
+
+  vendor_reloc_iterator(MutableArrayRef<Relocation>::iterator i,
+                        MutableArrayRef<Relocation>::iterator e)
+      : it(i), end(e) {}
+
+  // Dereference
+  Relocation operator*() const {
+    Relocation r = *it;
+    r.type.v |= rvVendorFlag;
+    return r;
+  }
+
+  struct vendor_reloc_proxy {
+    Relocation r;
+    const Relocation *operator->() const { return &r; }
+  };
+
+  vendor_reloc_proxy operator->() const {
+    return vendor_reloc_proxy{this->operator*()};
+  }
+
+  vendor_reloc_iterator &operator++() {
+    ++it;
+    if (it != end && it->type == llvm::ELF::R_RISCV_VENDOR) {
+      rvVendorFlag = getRISCVVendorRelMarker(it->sym->getName());
+      ++it;
+    } else {
+      rvVendorFlag = 0;
+    }
+    return *this;
+  }
+
+  vendor_reloc_iterator operator++(int) {
+    vendor_reloc_iterator tmp(*this);
+    ++(*this);
+    return tmp;
+  }
+
+  bool operator==(const vendor_reloc_iterator &other) const {
+    return it == other.it;
+  }
+  bool operator!=(const vendor_reloc_iterator &other) const {
+    return it != other.it;
+  }
+
+  Relocation *getUnderlyingRelocation() const { return &*it; }
+
+private:
+  MutableArrayRef<Relocation>::iterator it;
+  MutableArrayRef<Relocation>::iterator end;
+  uint32_t rvVendorFlag = 0;
+};
+
+inline auto riscv_vendor_relocs(MutableArrayRef<Relocation> arr) {
+  return llvm::make_range(vendor_reloc_iterator(arr.begin(), arr.end()),
+                          vendor_reloc_iterator(arr.end(), arr.end()));
+}
+
+} // namespace lld::elf
+
+#endif
----------------
lenary wrote:

Newline at EOF

https://github.com/llvm/llvm-project/pull/169273