Auto merge of #139275 - cuviper:min-llvm-19, r=nikic

Update the minimum external LLVM to 19

With this change, we'll have stable support for LLVM 19 and 20.
For reference, the previous increase to LLVM 18 was #130487.

cc `@rust-lang/wg-llvm`
r? nikic

1 files changed, 14 insertions, 44 deletions

diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index 257bdc01993..e02c80c50b1 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -47,10 +47,7 @@
 #include <vector>
 
 // Conditional includes prevent clang-format from fully sorting the list,
-// so keep them separate.
-#if LLVM_VERSION_GE(19, 0)
-#include "llvm/Support/PGOOptions.h"
-#endif
+// so if any are needed, keep them separate down here.
 
 using namespace llvm;
 
@@ -432,31 +429,15 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
   }
   if (!strcmp("zlib", DebugInfoCompression) &&
       llvm::compression::zlib::isAvailable()) {
-#if LLVM_VERSION_GE(19, 0)
     Options.MCOptions.CompressDebugSections = DebugCompressionType::Zlib;
-#else
-    Options.CompressDebugSections = DebugCompressionType::Zlib;
-#endif
   } else if (!strcmp("zstd", DebugInfoCompression) &&
              llvm::compression::zstd::isAvailable()) {
-#if LLVM_VERSION_GE(19, 0)
     Options.MCOptions.CompressDebugSections = DebugCompressionType::Zstd;
-#else
-    Options.CompressDebugSections = DebugCompressionType::Zstd;
-#endif
   } else if (!strcmp("none", DebugInfoCompression)) {
-#if LLVM_VERSION_GE(19, 0)
     Options.MCOptions.CompressDebugSections = DebugCompressionType::None;
-#else
-    Options.CompressDebugSections = DebugCompressionType::None;
-#endif
   }
 
-#if LLVM_VERSION_GE(19, 0)
   Options.MCOptions.X86RelaxRelocations = RelaxELFRelocations;
-#else
-  Options.RelaxELFRelocations = RelaxELFRelocations;
-#endif
   Options.UseInitArray = UseInitArray;
   Options.EmulatedTLS = UseEmulatedTls;
 
@@ -753,34 +734,23 @@ extern "C" LLVMRustResult LLVMRustOptimize(
   auto FS = vfs::getRealFileSystem();
   if (PGOGenPath) {
     assert(!PGOUsePath && !PGOSampleUsePath);
-    PGOOpt = PGOOptions(PGOGenPath, "", "", "", FS, PGOOptions::IRInstr,
-                        PGOOptions::NoCSAction,
-#if LLVM_VERSION_GE(19, 0)
-                        PGOOptions::ColdFuncOpt::Default,
-#endif
-                        DebugInfoForProfiling);
+    PGOOpt = PGOOptions(
+        PGOGenPath, "", "", "", FS, PGOOptions::IRInstr, PGOOptions::NoCSAction,
+        PGOOptions::ColdFuncOpt::Default, DebugInfoForProfiling);
   } else if (PGOUsePath) {
     assert(!PGOSampleUsePath);
-    PGOOpt = PGOOptions(PGOUsePath, "", "", "", FS, PGOOptions::IRUse,
-                        PGOOptions::NoCSAction,
-#if LLVM_VERSION_GE(19, 0)
-                        PGOOptions::ColdFuncOpt::Default,
-#endif
-                        DebugInfoForProfiling);
+    PGOOpt = PGOOptions(
+        PGOUsePath, "", "", "", FS, PGOOptions::IRUse, PGOOptions::NoCSAction,
+        PGOOptions::ColdFuncOpt::Default, DebugInfoForProfiling);
   } else if (PGOSampleUsePath) {
-    PGOOpt = PGOOptions(PGOSampleUsePath, "", "", "", FS, PGOOptions::SampleUse,
-                        PGOOptions::NoCSAction,
-#if LLVM_VERSION_GE(19, 0)
-                        PGOOptions::ColdFuncOpt::Default,
-#endif
-                        DebugInfoForProfiling);
+    PGOOpt =
+        PGOOptions(PGOSampleUsePath, "", "", "", FS, PGOOptions::SampleUse,
+                   PGOOptions::NoCSAction, PGOOptions::ColdFuncOpt::Default,
+                   DebugInfoForProfiling);
   } else if (DebugInfoForProfiling) {
-    PGOOpt = PGOOptions("", "", "", "", FS, PGOOptions::NoAction,
-                        PGOOptions::NoCSAction,
-#if LLVM_VERSION_GE(19, 0)
-                        PGOOptions::ColdFuncOpt::Default,
-#endif
-                        DebugInfoForProfiling);
+    PGOOpt = PGOOptions(
+        "", "", "", "", FS, PGOOptions::NoAction, PGOOptions::NoCSAction,
+        PGOOptions::ColdFuncOpt::Default, DebugInfoForProfiling);
   }
 
   auto PB = PassBuilder(TM, PTO, PGOOpt, &PIC);