diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/context.rs | 27 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/intrinsic.rs | 78 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/llvm/ffi.rs | 1 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/type_.rs | 4 |
4 files changed, 102 insertions, 8 deletions
diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs index e8a7afcc632..287a22bc9a6 100644 --- a/compiler/rustc_codegen_llvm/src/context.rs +++ b/compiler/rustc_codegen_llvm/src/context.rs @@ -8,7 +8,7 @@ use crate::llvm_util; use crate::type_::Type; use crate::value::Value; -use rustc_codegen_ssa::base::wants_msvc_seh; +use rustc_codegen_ssa::base::{wants_msvc_seh, wants_wasm_eh}; use rustc_codegen_ssa::traits::*; use rustc_data_structures::base_n; use rustc_data_structures::fx::FxHashMap; @@ -532,19 +532,28 @@ impl<'ll, 'tcx> MiscMethods<'tcx> for CodegenCx<'ll, 'tcx> { if let Some(llpersonality) = self.eh_personality.get() { return llpersonality; } + + let name = if wants_msvc_seh(self.sess()) { + Some("__CxxFrameHandler3") + } else if wants_wasm_eh(self.sess()) { + // LLVM specifically tests for the name of the personality function + // There is no need for this function to exist anywhere, it will + // not be called. However, its name has to be "__gxx_wasm_personality_v0" + // for native wasm exceptions. + Some("__gxx_wasm_personality_v0") + } else { + None + }; + let tcx = self.tcx; let llfn = match tcx.lang_items().eh_personality() { - Some(def_id) if !wants_msvc_seh(self.sess()) => self.get_fn_addr( + Some(def_id) if name.is_none() => self.get_fn_addr( ty::Instance::resolve(tcx, ty::ParamEnv::reveal_all(), def_id, ty::List::empty()) .unwrap() .unwrap(), ), _ => { - let name = if wants_msvc_seh(self.sess()) { - "__CxxFrameHandler3" - } else { - "rust_eh_personality" - }; + let name = name.unwrap_or("rust_eh_personality"); if let Some(llfn) = self.get_declared_value(name) { llfn } else { @@ -662,6 +671,10 @@ impl<'ll> CodegenCx<'ll, '_> { let t_f32 = self.type_f32(); let t_f64 = self.type_f64(); let t_metadata = self.type_metadata(); + let t_token = self.type_token(); + + ifn!("llvm.wasm.get.exception", fn(t_token) -> i8p); + ifn!("llvm.wasm.get.ehselector", fn(t_token) -> t_i32); ifn!("llvm.wasm.trunc.unsigned.i32.f32", fn(t_f32) -> t_i32); ifn!("llvm.wasm.trunc.unsigned.i32.f64", fn(t_f64) -> t_i32); diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs index 4e28034a850..31bafa87814 100644 --- a/compiler/rustc_codegen_llvm/src/intrinsic.rs +++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs @@ -7,7 +7,7 @@ use crate::type_of::LayoutLlvmExt; use crate::va_arg::emit_va_arg; use crate::value::Value; -use rustc_codegen_ssa::base::{compare_simd_types, wants_msvc_seh}; +use rustc_codegen_ssa::base::{compare_simd_types, wants_msvc_seh, wants_wasm_eh}; use rustc_codegen_ssa::common::{IntPredicate, TypeKind}; use rustc_codegen_ssa::errors::{ExpectedPointerMutability, InvalidMonomorphization}; use rustc_codegen_ssa::mir::operand::OperandRef; @@ -452,6 +452,8 @@ fn try_intrinsic<'ll>( bx.store(bx.const_i32(0), dest, ret_align); } else if wants_msvc_seh(bx.sess()) { codegen_msvc_try(bx, try_func, data, catch_func, dest); + } else if wants_wasm_eh(bx.sess()) { + codegen_wasm_try(bx, try_func, data, catch_func, dest); } else if bx.sess().target.os == "emscripten" { codegen_emcc_try(bx, try_func, data, catch_func, dest); } else { @@ -610,6 +612,80 @@ fn codegen_msvc_try<'ll>( bx.store(ret, dest, i32_align); } +// WASM's definition of the `rust_try` function. +fn codegen_wasm_try<'ll>( + bx: &mut Builder<'_, 'll, '_>, + try_func: &'ll Value, + data: &'ll Value, + catch_func: &'ll Value, + dest: &'ll Value, +) { + let (llty, llfn) = get_rust_try_fn(bx, &mut |mut bx| { + bx.set_personality_fn(bx.eh_personality()); + + let normal = bx.append_sibling_block("normal"); + let catchswitch = bx.append_sibling_block("catchswitch"); + let catchpad = bx.append_sibling_block("catchpad"); + let caught = bx.append_sibling_block("caught"); + + let try_func = llvm::get_param(bx.llfn(), 0); + let data = llvm::get_param(bx.llfn(), 1); + let catch_func = llvm::get_param(bx.llfn(), 2); + + // We're generating an IR snippet that looks like: + // + // declare i32 @rust_try(%try_func, %data, %catch_func) { + // %slot = alloca i8* + // invoke %try_func(%data) to label %normal unwind label %catchswitch + // + // normal: + // ret i32 0 + // + // catchswitch: + // %cs = catchswitch within none [%catchpad] unwind to caller + // + // catchpad: + // %tok = catchpad within %cs [null] + // %ptr = call @llvm.wasm.get.exception(token %tok) + // %sel = call @llvm.wasm.get.ehselector(token %tok) + // call %catch_func(%data, %ptr) + // catchret from %tok to label %caught + // + // caught: + // ret i32 1 + // } + // + let try_func_ty = bx.type_func(&[bx.type_i8p()], bx.type_void()); + bx.invoke(try_func_ty, None, None, try_func, &[data], normal, catchswitch, None); + + bx.switch_to_block(normal); + bx.ret(bx.const_i32(0)); + + bx.switch_to_block(catchswitch); + let cs = bx.catch_switch(None, None, &[catchpad]); + + bx.switch_to_block(catchpad); + let null = bx.const_null(bx.type_i8p()); + let funclet = bx.catch_pad(cs, &[null]); + + let ptr = bx.call_intrinsic("llvm.wasm.get.exception", &[funclet.cleanuppad()]); + let _sel = bx.call_intrinsic("llvm.wasm.get.ehselector", &[funclet.cleanuppad()]); + + let catch_ty = bx.type_func(&[bx.type_i8p(), bx.type_i8p()], bx.type_void()); + bx.call(catch_ty, None, None, catch_func, &[data, ptr], Some(&funclet)); + bx.catch_ret(&funclet, caught); + + bx.switch_to_block(caught); + bx.ret(bx.const_i32(1)); + }); + + // Note that no invoke is used here because by definition this function + // can't panic (that's what it's catching). + let ret = bx.call(llty, None, None, llfn, &[try_func, data, catch_func], None); + let i32_align = bx.tcx().data_layout.i32_align.abi; + bx.store(ret, dest, i32_align); +} + // Definition of the standard `try` function for Rust using the GNU-like model // of exceptions (e.g., the normal semantics of LLVM's `landingpad` and `invoke` // instructions). diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs index fdc5f3b193e..08f47adcc04 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs @@ -1071,6 +1071,7 @@ extern "C" { // Operations on other types pub fn LLVMVoidTypeInContext(C: &Context) -> &Type; + pub fn LLVMTokenTypeInContext(C: &Context) -> &Type; pub fn LLVMMetadataTypeInContext(C: &Context) -> &Type; // Operations on all values diff --git a/compiler/rustc_codegen_llvm/src/type_.rs b/compiler/rustc_codegen_llvm/src/type_.rs index 4ffa2b9c6a3..7e672a8dc33 100644 --- a/compiler/rustc_codegen_llvm/src/type_.rs +++ b/compiler/rustc_codegen_llvm/src/type_.rs @@ -52,6 +52,10 @@ impl<'ll> CodegenCx<'ll, '_> { unsafe { llvm::LLVMVoidTypeInContext(self.llcx) } } + pub(crate) fn type_token(&self) -> &'ll Type { + unsafe { llvm::LLVMTokenTypeInContext(self.llcx) } + } + pub(crate) fn type_metadata(&self) -> &'ll Type { unsafe { llvm::LLVMMetadataTypeInContext(self.llcx) } } |