all: add full LLVM 20 support

This switches the Espressif fork from LLVM 19 to LLVM 20, so we can use
the improvements made between those LLVM versions. It also better aligns
with the system-LLVM build method, which currently also defaults to LLVM
20.

Note that this disables the machine outliner for RISC-V. It appears
there's a bug in there somewhere, with the machine outliner enabled the
crypto/elliptic package tests fail with -target=riscv-qemu.
This should ideally be investigated and reported upstream.

builder/cc1as.cpp

@@ -144,8 +144,6 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
             .Default(llvm::DebugCompressionType::None);
   }
 
-  Opts.RelaxELFRelocations = !Args.hasArg(OPT_mrelax_relocations_no);
-  Opts.SSE2AVX = Args.hasArg(OPT_msse2avx);
   if (auto *DwarfFormatArg = Args.getLastArg(OPT_gdwarf64, OPT_gdwarf32))
     Opts.Dwarf64 = DwarfFormatArg->getOption().matches(OPT_gdwarf64);
   Opts.DwarfVersion = getLastArgIntValue(Args, OPT_dwarf_version_EQ, 2, Diags);
@@ -236,6 +234,9 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
   Opts.EmitCompactUnwindNonCanonical =
       Args.hasArg(OPT_femit_compact_unwind_non_canonical);
   Opts.Crel = Args.hasArg(OPT_crel);
+  Opts.ImplicitMapsyms = Args.hasArg(OPT_mmapsyms_implicit);
+  Opts.X86RelaxRelocations = !Args.hasArg(OPT_mrelax_relocations_no);
+  Opts.X86Sse2Avx = Args.hasArg(OPT_msse2avx);
 
   Opts.AsSecureLogFile = Args.getLastArgValue(OPT_as_secure_log_file);
 
@@ -294,8 +295,9 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
   MCOptions.EmitCompactUnwindNonCanonical = Opts.EmitCompactUnwindNonCanonical;
   MCOptions.MCSaveTempLabels = Opts.SaveTemporaryLabels;
   MCOptions.Crel = Opts.Crel;
-  MCOptions.X86RelaxRelocations = Opts.RelaxELFRelocations;
-  MCOptions.X86Sse2Avx = Opts.SSE2AVX;
+  MCOptions.ImplicitMapSyms = Opts.ImplicitMapsyms;
+  MCOptions.X86RelaxRelocations = Opts.X86RelaxRelocations;
+  MCOptions.X86Sse2Avx = Opts.X86Sse2Avx;
   MCOptions.CompressDebugSections = Opts.CompressDebugSections;
   MCOptions.AsSecureLogFile = Opts.AsSecureLogFile;
 
@@ -343,10 +345,6 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
   // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
   std::unique_ptr<MCObjectFileInfo> MOFI(
       TheTarget->createMCObjectFileInfo(Ctx, PIC));
-  if (Opts.DarwinTargetVariantTriple)
-    MOFI->setDarwinTargetVariantTriple(*Opts.DarwinTargetVariantTriple);
-  if (!Opts.DarwinTargetVariantSDKVersion.empty())
-    MOFI->setDarwinTargetVariantSDKVersion(Opts.DarwinTargetVariantSDKVersion);
   Ctx.setObjectFileInfo(MOFI.get());
 
   if (Opts.GenDwarfForAssembly)
@@ -428,6 +426,13 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
     Str.reset(TheTarget->createMCObjectStreamer(
         T, Ctx, std::move(MAB), std::move(OW), std::move(CE), *STI));
     Str.get()->initSections(Opts.NoExecStack, *STI);
+    if (T.isOSBinFormatMachO() && T.isOSDarwin()) {
+      Triple *TVT = Opts.DarwinTargetVariantTriple
+                        ? &*Opts.DarwinTargetVariantTriple
+                        : nullptr;
+      Str->emitVersionForTarget(T, VersionTuple(), TVT,
+                                Opts.DarwinTargetVariantSDKVersion);
+    }
   }
 
   // When -fembed-bitcode is passed to clang_as, a 1-byte marker

builder/cc1as.h

@@ -45,10 +45,6 @@ struct AssemblerInvocation {
   LLVM_PREFERRED_TYPE(bool)
   unsigned GenDwarfForAssembly : 1;
   LLVM_PREFERRED_TYPE(bool)
-  unsigned RelaxELFRelocations : 1;
-  LLVM_PREFERRED_TYPE(bool)
-  unsigned SSE2AVX : 1;
-  LLVM_PREFERRED_TYPE(bool)
   unsigned Dwarf64 : 1;
   unsigned DwarfVersion;
   std::string DwarfDebugFlags;
@@ -117,6 +113,13 @@ struct AssemblerInvocation {
 
   LLVM_PREFERRED_TYPE(bool)
   unsigned Crel : 1;
+  LLVM_PREFERRED_TYPE(bool)
+  unsigned ImplicitMapsyms : 1;
+
+  LLVM_PREFERRED_TYPE(bool)
+  unsigned X86RelaxRelocations : 1;
+  LLVM_PREFERRED_TYPE(bool)
+  unsigned X86Sse2Avx : 1;
 
   /// The name of the relocation model to use.
   std::string RelocationModel;
@@ -148,7 +151,6 @@ public:
     ShowInst = 0;
     ShowEncoding = 0;
     RelaxAll = 0;
-    SSE2AVX = 0;
     NoExecStack = 0;
     FatalWarnings = 0;
     NoWarn = 0;
@@ -160,6 +162,9 @@ public:
     EmitDwarfUnwind = EmitDwarfUnwindType::Default;
     EmitCompactUnwindNonCanonical = false;
     Crel = false;
+    ImplicitMapsyms = 0;
+    X86RelaxRelocations = 0;
+    X86Sse2Avx = 0;
   }
 
   static bool CreateFromArgs(AssemblerInvocation &Res,

builder/clang.cpp

@@ -60,7 +60,7 @@ bool tinygo_clang_driver(int argc, char **argv) {
 			}
 
 			// Create the actual diagnostics engine.
-			Clang->createDiagnostics();
+			Clang->createDiagnostics(*llvm::vfs::getRealFileSystem());
 			if (!Clang->hasDiagnostics()) {
 				return false;
 			}

builder/sizes_test.go

@@ -42,9 +42,9 @@ func TestBinarySize(t *testing.T) {
 	// This is a small number of very diverse targets that we want to test.
 	tests := []sizeTest{
 		// microcontrollers
-		{"hifive1b", "examples/echo", 4580, 280, 0, 2264},
-		{"microbit", "examples/serial", 2928, 388, 8, 2272},
-		{"wioterminal", "examples/pininterrupt", 7387, 1489, 116, 6912},
+		{"hifive1b", "examples/echo", 3884, 280, 0, 2268},
+		{"microbit", "examples/serial", 2924, 388, 8, 2272},
+		{"wioterminal", "examples/pininterrupt", 7365, 1491, 116, 6912},
 
 		// TODO: also check wasm. Right now this is difficult, because
 		// wasm binaries are run through wasm-opt and therefore the