internal/rosa: initial cross-compilation support

This successfully cross-compiles the toolchain. More work is needed to
support cross-compilation on all native helpers and existing packages.

Signed-off-by: Ophestra <cat@gensokyo.uk>

1 files changed, 95 insertions, 34 deletions

diff --git a/internal/rosa/llvm.go b/internal/rosa/llvm.go
index d9ca83e1..4d3e4b21 100644
--- a/internal/rosa/llvm.go
+++ b/internal/rosa/llvm.go
@@ -75,53 +75,112 @@ func init() {
 
 		target := t.triple()
 		cache := []KV{
-			{"ENABLE_LINKER_BUILD_ID", "ON"},
-			{"COMPILER_RT_USE_BUILTINS_LIBRARY", "ON"},
-			{"COMPILER_RT_DEFAULT_TARGET_ONLY", "ON"},
-			{"COMPILER_RT_BUILD_GWP_ASAN", "OFF"},
-			{"LIBCXX_CXX_ABI", "libcxxabi"},
-			{"LIBCXX_USE_COMPILER_RT", "ON"},
-			{"LIBCXX_ENABLE_STATIC_ABI_LIBRARY", "OFF"},
-			{"LIBCXX_HAS_MUSL_LIBC", "ON"},
-			{"LIBCXX_HARDENING_MODE", "fast"},
-			{"LIBCXX_STATICALLY_LINK_ABI_IN_STATIC_LIBRARY", "ON"},
-			{"LIBCXXABI_USE_LLVM_UNWINDER", "ON"},
-			{"LIBCXXABI_ENABLE_STATIC_UNWINDER", "ON"},
-			{"LIBCXXABI_USE_COMPILER_RT", "ON"},
-			{"LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY", "ON"},
+			{"LLVM_HOST_TRIPLE", "'" + target + "'"},
+			{"LLVM_ENABLE_PROJECTS", "'" + strings.Join([]string{
+				"clang",
+				"lld",
+			}, ";") + "'"},
+			{"LLVM_ENABLE_RUNTIMES", "'" + strings.Join([]string{
+				"compiler-rt",
+				"libcxx",
+				"libcxxabi",
+				"libunwind",
+			}, ";") + "'"},
+
+			{"LLVM_ENABLE_LLD", "ON"},
 			{"LLVM_INSTALL_BINUTILS_SYMLINKS", "ON"},
 			{"LLVM_INSTALL_UTILS", "ON"},
+
+			{"CLANG_DEFAULT_RTLIB", "compiler-rt"},
+			{"CLANG_DEFAULT_UNWINDLIB", "libunwind"},
+			{"CLANG_DEFAULT_CXX_STDLIB", "libc++"},
+			{"CLANG_CONFIG_FILE_SYSTEM_DIR", "/system/etc/clang"},
+		}
+
+		common := []KV{
+			{"CMAKE_POSITION_INDEPENDENT_CODE", "ON"},
+
 			{"LLVM_BUILD_LLVM_DYLIB", "ON"},
 			{"LLVM_LINK_LLVM_DYLIB", "ON"},
 			{"LLVM_APPEND_VC_REV", "OFF"},
+			{"LLVM_ENABLE_PER_TARGET_RUNTIME_DIR", "ON"},
+			{"LLVM_INCLUDE_BENCHMARKS", "OFF"},
 			{"LLVM_ENABLE_RTTI", "ON"},
 			{"LLVM_ENABLE_ZLIB", "FORCE_ON"},
 			{"LLVM_ENABLE_ZSTD", "FORCE_ON"},
-			{"LLVM_ENABLE_PER_TARGET_RUNTIME_DIR", "ON"},
-			{"LLVM_INCLUDE_BENCHMARKS", "OFF"},
-			{"CLANG_DEFAULT_RTLIB", "compiler-rt"},
-			{"CLANG_DEFAULT_UNWINDLIB", "libunwind"},
-			{"CLANG_DEFAULT_CXX_STDLIB", "libc++"},
-			{"CLANG_CONFIG_FILE_SYSTEM_DIR", "/system/etc/clang"},
 			{"LLVM_ENABLE_FFI", "OFF"},
 			{"LLVM_ENABLE_LIBXML2", "OFF"},
 			{"LLVM_ENABLE_LIBCXX", "ON"},
-			{"LLVM_ENABLE_LLD", "ON"},
+
+			{"COMPILER_RT_USE_BUILTINS_LIBRARY", "ON"},
+			{"COMPILER_RT_DEFAULT_TARGET_ONLY", "ON"},
+			{"COMPILER_RT_BUILD_GWP_ASAN", "OFF"},
+			// symbols: clock_gettime, mallopt
+			{"COMPILER_RT_INCLUDE_TESTS", "OFF"},
+
 			{"LIBUNWIND_ENABLE_ASSERTIONS", "OFF"},
 			{"LIBUNWIND_USE_COMPILER_RT", "ON"},
 
-			{"LLVM_HOST_TRIPLE", "'" + target + "'"},
-			{"LLVM_ENABLE_PROJECTS", "'" + strings.Join([]string{
-				"clang",
-				"lld",
-			}, ";") + "'"},
-			{"LLVM_ENABLE_RUNTIMES", "'" + strings.Join([]string{
-				"compiler-rt",
-				"libcxx",
-				"libcxxabi",
-				"libunwind",
-			}, ";") + "'"},
+			{"LIBCXX_CXX_ABI", "libcxxabi"},
+			{"LIBCXX_USE_COMPILER_RT", "ON"},
+			{"LIBCXX_ENABLE_STATIC_ABI_LIBRARY", "OFF"},
+			{"LIBCXX_HAS_MUSL_LIBC", "ON"},
+			{"LIBCXX_HARDENING_MODE", "fast"},
+			{"LIBCXX_STATICALLY_LINK_ABI_IN_STATIC_LIBRARY", "ON"},
+
+			{"LIBCXXABI_USE_LLVM_UNWINDER", "ON"},
+			{"LIBCXXABI_ENABLE_STATIC_UNWINDER", "ON"},
+			{"LIBCXXABI_USE_COMPILER_RT", "ON"},
+			{"LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY", "ON"},
+		}
+		cache = append(cache, common...)
+
+		var (
+			triples []string
+			paths   []pkg.ExecPath
+		)
+		for _, arch := range []string{
+			"amd64",
+			"arm64",
+			"riscv64",
+		} {
+			_triple := triple(arch)
+			triples = append(triples, _triple)
+			if t.stage.isStage0() {
+				continue
+			}
+
+			if arch != t.Arch() {
+				sysroot := AbsSystem.Append(arch)
+				ct := t.native()
+				if ct.Arch() != arch {
+					ct = t.NewCross(arch).New(t.stage)
+				}
+				paths = append(paths, pkg.Path(
+					sysroot, true, ct.Append(nil,
+						_musl,
+						_kernelHeaders,
+					)...,
+				))
+				cache = append(cache, []KV{
+					{"BUILTINS_" + _triple + "_CMAKE_SYSROOT", sysroot.String()},
+					{"RUNTIMES_" + _triple + "_CMAKE_SYSROOT", sysroot.String()},
+					{"RUNTIMES_" + _triple + "_LLVM_INCLUDE_TESTS", "OFF"},
+				}...)
+			}
+
+			cache = append(cache, []KV{
+				{"BUILTINS_" + _triple + "_CMAKE_BUILD_TYPE", "Release"},
+				{"RUNTIMES_" + _triple + "_CMAKE_BUILD_TYPE", "Release"},
+				{"RUNTIMES_" + _triple + "_CXX_SUPPORTS_FNO_EXCEPTIONS_FLAG", "ON"},
+				{"RUNTIMES_" + _triple + "_CXX_SUPPORTS_FUNWIND_TABLES_FLAG", "ON"},
+			}...)
+			for _, p := range common {
+				p[0] = "RUNTIMES_" + _triple + "_" + p[0]
+				cache = append(cache, p)
+			}
 		}
+		targets := strings.Join(triples, ";")
 
 		if !t.stage.isStage0() {
 			skipChecks := []string{
@@ -181,9 +240,10 @@ func init() {
 			}
 
 			cache = append(cache, []KV{
-				// symbols: clock_gettime, mallopt
-				{"COMPILER_RT_INCLUDE_TESTS", "OFF"},
+				{"CLANG_VENDOR", "'Rosa OS'"},
 
+				{"LLVM_BUILTIN_TARGETS", "'" + targets + "'"},
+				{"LLVM_RUNTIME_TARGETS", "'" + targets + "'"},
 				{"LLVM_BUILD_TESTS", "ON"},
 				{"LLVM_LIT_ARGS", litArgs(true, skipChecks...)},
 			}...)
@@ -198,6 +258,7 @@ func init() {
 				"tr",
 				"awk",
 			},
+			Paths: paths,
 
 			ScriptEarly: `
 rm -f /system/bin/clang++.cfg