diff options
| -rw-r--r-- | src/back/write.rs | 54 |
1 files changed, 51 insertions, 3 deletions
diff --git a/src/back/write.rs b/src/back/write.rs index 33e76c4565c..2fa2bf651d5 100644 --- a/src/back/write.rs +++ b/src/back/write.rs @@ -1,6 +1,6 @@ use std::{env, fs}; -use gccjit::OutputKind; +use gccjit::{Context, OutputKind}; use rustc_codegen_ssa::back::link::ensure_removed; use rustc_codegen_ssa::back::write::{BitcodeSection, CodegenContext, EmitObj, ModuleConfig}; use rustc_codegen_ssa::{CompiledModule, ModuleCodegen}; @@ -176,10 +176,58 @@ pub(crate) unsafe fn codegen( context.add_driver_option("-nostdlib"); // NOTE: this doesn't actually generate an executable. With the above flags, it combines the .o files together in another .o. - context.compile_to_file( + // FIXME FIXME: this produces an object file with GIMPLE IR, but it should + // produce an object file with machine code. + //println!("LTO-ed object file: {:?}", obj_out); + /*context.compile_to_file( OutputKind::Executable, obj_out.to_str().expect("path to str"), - ); + );*/ + + let path = obj_out.to_str().expect("path to str"); + + if fat_lto { + let lto_path = format!("{}.lto", path); + // FIXME(antoyo): The LTO frontend generates the following warning: + // ../build_sysroot/sysroot_src/library/core/src/num/dec2flt/lemire.rs:150:15: warning: type of ‘_ZN4core3num7dec2flt5table17POWER_OF_FIVE_12817ha449a68fb31379e4E’ does not match original declaration [-Wlto-type-mismatch] + // 150 | let (lo5, hi5) = POWER_OF_FIVE_128[index]; + // | ^ + // lto1: note: ‘_ZN4core3num7dec2flt5table17POWER_OF_FIVE_12817ha449a68fb31379e4E’ was previously declared here + // + // This option is to mute it to make the UI tests pass with LTO enabled. + context.add_driver_option("-Wno-lto-type-mismatch"); + // NOTE: this doesn't actually generate an executable. With the above + // flags, it combines the .o files together in another .o. + context.compile_to_file(OutputKind::Executable, <o_path); + + let context = Context::default(); // TODO: might need to set some other flags from new_context. + //context.add_driver_option("-v"); + //println!("*** Arch: {}", cgcx.target_arch); + if cgcx.target_arch == "x86" || cgcx.target_arch == "x86_64" { + //println!("**** Added -masm=intel"); + //context.add_command_line_option("-masm=intel"); + // NOTE: it seems we need to use add_driver_option instead of + // add_command_line_option here because we use the LTO frontend via gcc. + context.add_driver_option("-masm=intel"); + } + + // NOTE: these two options are needed to invoke LTO to produce an object file. + // We need to initiate a second compilation because the arguments "-x lto" + // needs to be at the very beginning. + // TODO TODO: check that LTO still does the optimizations across different + // object files with this change. + // TODO: this should probably be in a condition `if fat_lto`. + context.add_driver_option("-x"); + context.add_driver_option("lto"); + context.add_driver_option("-fPIC"); // TODO TODO: only add this flag when necessary. + context.add_driver_option(lto_path); + + context.compile_to_file(OutputKind::ObjectFile, path); + } else { + // NOTE: this doesn't actually generate an executable. With the above + // flags, it combines the .o files together in another .o. + context.compile_to_file(OutputKind::Executable, path); + } } else { context.compile_to_file( OutputKind::ObjectFile, |