1 files changed, 42 insertions, 4 deletions
diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index 0df7b7eed11..cb7cce4da0d 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -250,8 +250,6 @@ static Attribute::AttrKind fromRust(LLVMRustAttribute Kind) {
     return Attribute::NonLazyBind;
   case OptimizeNone:
     return Attribute::OptimizeNone;
-  case ReturnsTwice:
-    return Attribute::ReturnsTwice;
   case ReadNone:
     return Attribute::ReadNone;
   case SanitizeHWAddress:
@@ -420,7 +418,11 @@ extern "C" LLVMAttributeRef LLVMRustCreateMemoryEffectsAttr(LLVMContextRef C,
   }
 }
 
-// Enable a fast-math flag
+// Enable all fast-math flags, including those which will cause floating-point operations
+// to return poison for some well-defined inputs. This function can only be used to build
+// unsafe Rust intrinsics. That unsafety does permit additional optimizations, but at the
+// time of writing, their value is not well-understood relative to those enabled by
+// LLVMRustSetAlgebraicMath.
 //
 // https://llvm.org/docs/LangRef.html#fast-math-flags
 extern "C" void LLVMRustSetFastMath(LLVMValueRef V) {
@@ -429,6 +431,39 @@ extern "C" void LLVMRustSetFastMath(LLVMValueRef V) {
   }
 }
 
+// Enable fast-math flags which permit algebraic transformations that are not allowed by
+// IEEE floating point. For example:
+// a + (b + c) = (a + b) + c
+// and
+// a / b = a * (1 / b)
+// Note that this does NOT enable any flags which can cause a floating-point operation on
+// well-defined inputs to return poison, and therefore this function can be used to build
+// safe Rust intrinsics (such as fadd_algebraic).
+//
+// https://llvm.org/docs/LangRef.html#fast-math-flags
+extern "C" void LLVMRustSetAlgebraicMath(LLVMValueRef V) {
+  if (auto I = dyn_cast<Instruction>(unwrap<Value>(V))) {
+    I->setHasAllowReassoc(true);
+    I->setHasAllowContract(true);
+    I->setHasAllowReciprocal(true);
+    I->setHasNoSignedZeros(true);
+  }
+}
+
+// Enable the reassoc fast-math flag, allowing transformations that pretend
+// floating-point addition and multiplication are associative.
+//
+// Note that this does NOT enable any flags which can cause a floating-point operation on
+// well-defined inputs to return poison, and therefore this function can be used to build
+// safe Rust intrinsics (such as fadd_algebraic).
+//
+// https://llvm.org/docs/LangRef.html#fast-math-flags
+extern "C" void LLVMRustSetAllowReassoc(LLVMValueRef V) {
+  if (auto I = dyn_cast<Instruction>(unwrap<Value>(V))) {
+    I->setHasAllowReassoc(true);
+  }
+}
+
 extern "C" LLVMValueRef
 LLVMRustBuildAtomicLoad(LLVMBuilderRef B, LLVMTypeRef Ty, LLVMValueRef Source,
                         const char *Name, LLVMAtomicOrdering Order) {
@@ -1227,7 +1262,7 @@ enum class LLVMRustDiagnosticLevel {
 extern "C" void
 LLVMRustUnpackInlineAsmDiagnostic(LLVMDiagnosticInfoRef DI,
                                   LLVMRustDiagnosticLevel *LevelOut,
-                                  unsigned *CookieOut,
+                                  uint64_t *CookieOut,
                                   LLVMTwineRef *MessageOut) {
   // Undefined to call this not on an inline assembly diagnostic!
   llvm::DiagnosticInfoInlineAsm *IA =
@@ -1803,6 +1838,9 @@ extern "C" LLVMRustResult LLVMRustWriteImportLibrary(
       std::string{},    // ExtName
       std::string{},    // SymbolName
       std::string{},    // AliasTarget
+#if LLVM_VERSION_GE(19, 0)
+      std::string{},    // ExportAs
+#endif
       ordinal,          // Ordinal
       ordinal_present,  // Noname
       false,            // Data