[lld] [llvm] [RISCV] Don't expose any constructors of RISCVISAInfo publicly. (PR #98249)

[Craig Topper via llvm-commits]

https://github.com/topperc created https://github.com/llvm/llvm-project/pull/98249

lld was using RISCVISAInfo(unsigned XLen, RISCVISAUtils::OrderedExtensionMap &Exts). This required a call to RISCVISAInfo::postProcessAndChecking to validate the RISCVISAInfo that was created. This exposes too much about RISCVISAInfo to lld.

Replace with a new RISCVISAInfo::createFromExtMap that is responsible for creating the object and calling postProcessAndChecking.

>From f1f94ec47c272cf0424a69b82bb2d487d6ded7c7 Mon Sep 17 00:00:00 2001
From: Craig Topper <craig.topper at sifive.com>
Date: Tue, 9 Jul 2024 16:55:39 -0700
Subject: [PATCH] [RISCV] Don't expose any constructors of RISCVISAInfo
 publicly.

lld was using RISCVISAInfo(unsigned XLen, RISCVISAUtils::OrderedExtensionMap &Exts).
This required a call to RISCVISAInfo::postProcessAndChecking to
validate the RISCVISAInfo that was created. This exposes too much
about RISCVISAInfo to lld.

Replace with a new RISCVISAInfo::createFromExtMap that is
responsible for creating the object and calling postProcessAndChecking.
---
 lld/ELF/Arch/RISCV.cpp                        |  5 ++---
 llvm/include/llvm/TargetParser/RISCVISAInfo.h | 12 +++++++-----
 llvm/lib/TargetParser/RISCVISAInfo.cpp        | 11 +++++++++++
 3 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/lld/ELF/Arch/RISCV.cpp b/lld/ELF/Arch/RISCV.cpp
index 07a1b63be8051..faacc8f834be7 100644
--- a/lld/ELF/Arch/RISCV.cpp
+++ b/lld/ELF/Arch/RISCV.cpp
@@ -1251,9 +1251,8 @@ mergeAttributesSection(const SmallVector<InputSectionBase *, 0> &sections) {
     }
   }
 
-  if (hasArch) {
-    if (auto result = RISCVISAInfo::postProcessAndChecking(
-            std::make_unique<RISCVISAInfo>(xlen, exts))) {
+  if (hasArch && xlen != 0) {
+    if (auto result = RISCVISAInfo::createFromExtMap(xlen, exts)) {
       merged.strAttr.try_emplace(RISCVAttrs::ARCH,
                                  saver().save((*result)->toString()));
     } else {
diff --git a/llvm/include/llvm/TargetParser/RISCVISAInfo.h b/llvm/include/llvm/TargetParser/RISCVISAInfo.h
index ba2965600decd..5d3f3e113e96d 100644
--- a/llvm/include/llvm/TargetParser/RISCVISAInfo.h
+++ b/llvm/include/llvm/TargetParser/RISCVISAInfo.h
@@ -26,9 +26,6 @@ class RISCVISAInfo {
   RISCVISAInfo(const RISCVISAInfo &) = delete;
   RISCVISAInfo &operator=(const RISCVISAInfo &) = delete;
 
-  RISCVISAInfo(unsigned XLen, RISCVISAUtils::OrderedExtensionMap &Exts)
-      : XLen(XLen), FLen(0), MinVLen(0), MaxELen(0), MaxELenFp(0), Exts(Exts) {}
-
   /// Parse RISC-V ISA info from arch string.
   /// If IgnoreUnknown is set, any unrecognised extension names or
   /// extensions with unrecognised versions will be silently dropped, except
@@ -48,6 +45,10 @@ class RISCVISAInfo {
   static llvm::Expected<std::unique_ptr<RISCVISAInfo>>
   parseFeatures(unsigned XLen, const std::vector<std::string> &Features);
 
+  static llvm::Expected<std::unique_ptr<RISCVISAInfo>>
+  createFromExtMap(unsigned XLen,
+                   const RISCVISAUtils::OrderedExtensionMap &Exts);
+
   /// Convert RISC-V ISA info to a feature vector.
   std::vector<std::string> toFeatures(bool AddAllExtensions = false,
                                       bool IgnoreUnknown = true) const;
@@ -72,8 +73,6 @@ class RISCVISAInfo {
   static bool isSupportedExtensionWithVersion(StringRef Ext);
   static bool isSupportedExtension(StringRef Ext, unsigned MajorVersion,
                                    unsigned MinorVersion);
-  static llvm::Expected<std::unique_ptr<RISCVISAInfo>>
-  postProcessAndChecking(std::unique_ptr<RISCVISAInfo> &&ISAInfo);
   static std::string getTargetFeatureForExtension(StringRef Ext);
 
 private:
@@ -93,6 +92,9 @@ class RISCVISAInfo {
 
   /// Update FLen, MinVLen, MaxELen, and MaxELenFp.
   void updateImpliedLengths();
+
+  static llvm::Expected<std::unique_ptr<RISCVISAInfo>>
+  postProcessAndChecking(std::unique_ptr<RISCVISAInfo> &&ISAInfo);
 };
 
 } // namespace llvm
diff --git a/llvm/lib/TargetParser/RISCVISAInfo.cpp b/llvm/lib/TargetParser/RISCVISAInfo.cpp
index 1d077326e4cf2..0229b5a140f91 100644
--- a/llvm/lib/TargetParser/RISCVISAInfo.cpp
+++ b/llvm/lib/TargetParser/RISCVISAInfo.cpp
@@ -395,6 +395,17 @@ static Error getExtensionVersion(StringRef Ext, StringRef In, unsigned &Major,
   return getError(Error);
 }
 
+llvm::Expected<std::unique_ptr<RISCVISAInfo>>
+RISCVISAInfo::createFromExtMap(unsigned XLen,
+                               const RISCVISAUtils::OrderedExtensionMap &Exts) {
+  assert(XLen == 32 || XLen == 64);
+  std::unique_ptr<RISCVISAInfo> ISAInfo(new RISCVISAInfo(XLen));
+
+  ISAInfo->Exts = Exts;
+
+  return RISCVISAInfo::postProcessAndChecking(std::move(ISAInfo));
+}
+
 llvm::Expected<std::unique_ptr<RISCVISAInfo>>
 RISCVISAInfo::parseFeatures(unsigned XLen,
                             const std::vector<std::string> &Features) {