Rollup merge of #122649 - cuviper:min-llvm-17, r=nikic

Update the minimum external LLVM to 17

With this change, we'll have stable support for LLVM 17 and 18.
For reference, the previous increase to LLVM 16 was #117947.

3 files changed, 4 insertions, 63 deletions

diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs
index f89c8c9f836..c3f17563b0a 100644
--- a/compiler/rustc_codegen_llvm/src/context.rs
+++ b/compiler/rustc_codegen_llvm/src/context.rs
@@ -126,17 +126,6 @@ pub unsafe fn create_module<'ll>(
 
     let mut target_data_layout = sess.target.data_layout.to_string();
     let llvm_version = llvm_util::get_version();
-    if llvm_version < (17, 0, 0) {
-        if sess.target.arch.starts_with("powerpc") {
-            // LLVM 17 specifies function pointer alignment for ppc:
-            // https://reviews.llvm.org/D147016
-            target_data_layout = target_data_layout
-                .replace("-Fn32", "")
-                .replace("-Fi32", "")
-                .replace("-Fn64", "")
-                .replace("-Fi64", "");
-        }
-    }
     if llvm_version < (18, 0, 0) {
         if sess.target.arch == "x86" || sess.target.arch == "x86_64" {
             // LLVM 18 adjusts i128 to be 128-bit aligned on x86 variants.
diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index f6253068eaa..067374c0261 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -24,9 +24,7 @@
 #include "llvm/Passes/StandardInstrumentations.h"
 #include "llvm/Support/CBindingWrapping.h"
 #include "llvm/Support/FileSystem.h"
-#if LLVM_VERSION_GE(17, 0)
 #include "llvm/Support/VirtualFileSystem.h"
-#endif
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Transforms/IPO/AlwaysInliner.h"
 #include "llvm/Transforms/IPO/FunctionImport.h"
@@ -334,14 +332,8 @@ extern "C" void LLVMRustPrintTargetCPUs(LLVMTargetMachineRef TM,
 
   std::ostringstream Buf;
 
-#if LLVM_VERSION_GE(17, 0)
   const MCSubtargetInfo *MCInfo = Target->getMCSubtargetInfo();
   const ArrayRef<SubtargetSubTypeKV> CPUTable = MCInfo->getAllProcessorDescriptions();
-#else
-  Buf << "Full target CPU help is not supported by this LLVM version.\n\n";
-  SubtargetSubTypeKV TargetCPUKV = { TargetCPU, {{}}, {{}} };
-  const ArrayRef<SubtargetSubTypeKV> CPUTable = TargetCPUKV;
-#endif
   unsigned MaxCPULen = getLongestEntryLength(CPUTable);
 
   Buf << "Available CPUs for this target:\n";
@@ -476,10 +468,6 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
   Options.RelaxELFRelocations = RelaxELFRelocations;
 #endif
   Options.UseInitArray = UseInitArray;
-
-#if LLVM_VERSION_LT(17, 0)
-  Options.ExplicitEmulatedTLS = true;
-#endif
   Options.EmulatedTLS = UseEmulatedTls;
 
   if (TrapUnreachable) {
@@ -761,16 +749,10 @@ LLVMRustOptimize(
   }
 
   std::optional<PGOOptions> PGOOpt;
-#if LLVM_VERSION_GE(17, 0)
   auto FS = vfs::getRealFileSystem();
-#endif
   if (PGOGenPath) {
     assert(!PGOUsePath && !PGOSampleUsePath);
-    PGOOpt = PGOOptions(PGOGenPath, "", "",
-#if LLVM_VERSION_GE(17, 0)
-                        "",
-                        FS,
-#endif
+    PGOOpt = PGOOptions(PGOGenPath, "", "", "", FS,
                         PGOOptions::IRInstr, PGOOptions::NoCSAction,
 #if LLVM_VERSION_GE(19, 0)
                         PGOOptions::ColdFuncOpt::Default,
@@ -778,33 +760,21 @@ LLVMRustOptimize(
                         DebugInfoForProfiling);
   } else if (PGOUsePath) {
     assert(!PGOSampleUsePath);
-    PGOOpt = PGOOptions(PGOUsePath, "", "",
-#if LLVM_VERSION_GE(17, 0)
-                        "",
-                        FS,
-#endif
+    PGOOpt = PGOOptions(PGOUsePath, "", "", "", FS,
                         PGOOptions::IRUse, PGOOptions::NoCSAction,
 #if LLVM_VERSION_GE(19, 0)
                         PGOOptions::ColdFuncOpt::Default,
 #endif
                         DebugInfoForProfiling);
   } else if (PGOSampleUsePath) {
-    PGOOpt = PGOOptions(PGOSampleUsePath, "", "",
-#if LLVM_VERSION_GE(17, 0)
-                        "",
-                        FS,
-#endif
+    PGOOpt = PGOOptions(PGOSampleUsePath, "", "", "", FS,
                         PGOOptions::SampleUse, PGOOptions::NoCSAction,
 #if LLVM_VERSION_GE(19, 0)
                         PGOOptions::ColdFuncOpt::Default,
 #endif
                         DebugInfoForProfiling);
   } else if (DebugInfoForProfiling) {
-    PGOOpt = PGOOptions("", "", "",
-#if LLVM_VERSION_GE(17, 0)
-                        "",
-                        FS,
-#endif
+    PGOOpt = PGOOptions("", "", "", "", FS,
                         PGOOptions::NoAction, PGOOptions::NoCSAction,
 #if LLVM_VERSION_GE(19, 0)
                         PGOOptions::ColdFuncOpt::Default,
@@ -1353,9 +1323,7 @@ LLVMRustCreateThinLTOData(LLVMRustThinLTOModule *modules,
   ComputeCrossModuleImport(
     Ret->Index,
     Ret->ModuleToDefinedGVSummaries,
-#if LLVM_VERSION_GE(17, 0)
     isPrevailing,
-#endif
     Ret->ImportLists,
     Ret->ExportLists
   );
diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index 91f54da5c12..f6ec410bfac 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -2152,19 +2152,3 @@ extern "C" LLVMValueRef LLVMConstStringInContext2(LLVMContextRef C,
   return wrap(ConstantDataArray::getString(*unwrap(C), StringRef(Str, Length), !DontNullTerminate));
 }
 #endif
-
-// FIXME: Remove when Rust's minimum supported LLVM version reaches 17.
-// https://github.com/llvm/llvm-project/commit/35276f16e5a2cae0dfb49c0fbf874d4d2f177acc
-#if LLVM_VERSION_LT(17, 0)
-extern "C" LLVMValueRef LLVMConstArray2(LLVMTypeRef ElementTy,
-                                        LLVMValueRef *ConstantVals,
-                                        uint64_t Length) {
-  ArrayRef<Constant *> V(unwrap<Constant>(ConstantVals, Length), Length);
-  return wrap(ConstantArray::get(ArrayType::get(unwrap(ElementTy), Length), V));
-}
-
-extern "C" LLVMTypeRef LLVMArrayType2(LLVMTypeRef ElementTy,
-                                      uint64_t ElementCount) {
-  return wrap(ArrayType::get(unwrap(ElementTy), ElementCount));
-}
-#endif