diff options
| -rw-r--r-- | compiler/rustc_mir_transform/src/instsimplify.rs | 13 | ||||
| -rw-r--r-- | tests/mir-opt/combine_transmutes.adt_transmutes.InstSimplify.diff | 166 | ||||
| -rw-r--r-- | tests/mir-opt/combine_transmutes.rs | 22 |
3 files changed, 49 insertions, 152 deletions
diff --git a/compiler/rustc_mir_transform/src/instsimplify.rs b/compiler/rustc_mir_transform/src/instsimplify.rs index 6bff535586a..e4dc617620e 100644 --- a/compiler/rustc_mir_transform/src/instsimplify.rs +++ b/compiler/rustc_mir_transform/src/instsimplify.rs @@ -5,7 +5,6 @@ use crate::MirPass; use rustc_hir::Mutability; use rustc_middle::mir::*; use rustc_middle::ty::layout::ValidityRequirement; -use rustc_middle::ty::util::IntTypeExt; use rustc_middle::ty::{self, ParamEnv, SubstsRef, Ty, TyCtxt}; use rustc_span::symbol::Symbol; use rustc_target::abi::FieldIdx; @@ -163,18 +162,6 @@ impl<'tcx> InstSimplifyContext<'tcx, '_> { return; } - // Transmuting a fieldless enum to its repr is a discriminant read - if let ty::Adt(adt_def, ..) = operand_ty.kind() - && adt_def.is_enum() - && adt_def.is_payloadfree() - && let Some(place) = operand.place() - && let Some(repr_int) = adt_def.repr().int - && repr_int.to_ty(self.tcx) == *cast_ty - { - *rvalue = Rvalue::Discriminant(place); - return; - } - // Transmuting a transparent struct/union to a field's type is a projection if let ty::Adt(adt_def, substs) = operand_ty.kind() && adt_def.repr().transparent() diff --git a/tests/mir-opt/combine_transmutes.adt_transmutes.InstSimplify.diff b/tests/mir-opt/combine_transmutes.adt_transmutes.InstSimplify.diff index c5907e7cf18..15117ea890e 100644 --- a/tests/mir-opt/combine_transmutes.adt_transmutes.InstSimplify.diff +++ b/tests/mir-opt/combine_transmutes.adt_transmutes.InstSimplify.diff @@ -4,59 +4,29 @@ fn adt_transmutes() -> () { let mut _0: (); // return place in scope 0 at $DIR/combine_transmutes.rs:+0:32: +0:32 let _1: u8; // in scope 0 at $DIR/combine_transmutes.rs:+1:9: +1:11 - let mut _2: EnumNoRepr; // in scope 0 at $DIR/combine_transmutes.rs:+1:28: +1:41 - let mut _4: EnumNoRepr; // in scope 0 at $DIR/combine_transmutes.rs:+2:28: +2:41 - let mut _6: EnumReprIsize; // in scope 0 at $DIR/combine_transmutes.rs:+3:31: +3:47 - let mut _8: EnumReprIsize; // in scope 0 at $DIR/combine_transmutes.rs:+4:31: +4:47 - let mut _10: std::cmp::Ordering; // in scope 0 at $DIR/combine_transmutes.rs:+5:28: +5:52 - let mut _12: std::cmp::Ordering; // in scope 0 at $DIR/combine_transmutes.rs:+6:28: +6:52 - let mut _14: std::option::Option<std::num::NonZeroU8>; // in scope 0 at $DIR/combine_transmutes.rs:+7:28: +7:58 - let mut _16: std::num::Wrapping<i16>; // in scope 0 at $DIR/combine_transmutes.rs:+8:29: +8:54 - let mut _18: std::num::Wrapping<i16>; // in scope 0 at $DIR/combine_transmutes.rs:+9:29: +9:54 - let mut _20: Union32; // in scope 0 at $DIR/combine_transmutes.rs:+10:29: +10:47 - let mut _22: Union32; // in scope 0 at $DIR/combine_transmutes.rs:+11:29: +11:47 - let mut _24: std::mem::MaybeUninit<std::string::String>; // in scope 0 at $DIR/combine_transmutes.rs:+12:46: +12:77 + let mut _2: std::option::Option<std::num::NonZeroU8>; // in scope 0 at $DIR/combine_transmutes.rs:+1:28: +1:58 + let mut _4: std::num::Wrapping<i16>; // in scope 0 at $DIR/combine_transmutes.rs:+2:29: +2:54 + let mut _6: std::num::Wrapping<i16>; // in scope 0 at $DIR/combine_transmutes.rs:+3:29: +3:54 + let mut _8: Union32; // in scope 0 at $DIR/combine_transmutes.rs:+4:29: +4:47 + let mut _10: Union32; // in scope 0 at $DIR/combine_transmutes.rs:+5:29: +5:47 + let mut _12: std::mem::MaybeUninit<std::string::String>; // in scope 0 at $DIR/combine_transmutes.rs:+6:46: +6:77 scope 1 { debug _a => _1; // in scope 1 at $DIR/combine_transmutes.rs:+1:9: +1:11 - let _3: i8; // in scope 1 at $DIR/combine_transmutes.rs:+2:9: +2:11 + let _3: i16; // in scope 1 at $DIR/combine_transmutes.rs:+2:9: +2:11 scope 2 { debug _a => _3; // in scope 2 at $DIR/combine_transmutes.rs:+2:9: +2:11 - let _5: usize; // in scope 2 at $DIR/combine_transmutes.rs:+3:9: +3:11 + let _5: u16; // in scope 2 at $DIR/combine_transmutes.rs:+3:9: +3:11 scope 3 { debug _a => _5; // in scope 3 at $DIR/combine_transmutes.rs:+3:9: +3:11 - let _7: isize; // in scope 3 at $DIR/combine_transmutes.rs:+4:9: +4:11 + let _7: u32; // in scope 3 at $DIR/combine_transmutes.rs:+4:9: +4:11 scope 4 { debug _a => _7; // in scope 4 at $DIR/combine_transmutes.rs:+4:9: +4:11 - let _9: u8; // in scope 4 at $DIR/combine_transmutes.rs:+5:9: +5:11 + let _9: i32; // in scope 4 at $DIR/combine_transmutes.rs:+5:9: +5:11 scope 5 { debug _a => _9; // in scope 5 at $DIR/combine_transmutes.rs:+5:9: +5:11 - let _11: i8; // in scope 5 at $DIR/combine_transmutes.rs:+6:9: +6:11 + let _11: std::mem::ManuallyDrop<std::string::String>; // in scope 5 at $DIR/combine_transmutes.rs:+6:9: +6:11 scope 6 { debug _a => _11; // in scope 6 at $DIR/combine_transmutes.rs:+6:9: +6:11 - let _13: u8; // in scope 6 at $DIR/combine_transmutes.rs:+7:9: +7:11 - scope 7 { - debug _a => _13; // in scope 7 at $DIR/combine_transmutes.rs:+7:9: +7:11 - let _15: i16; // in scope 7 at $DIR/combine_transmutes.rs:+8:9: +8:11 - scope 8 { - debug _a => _15; // in scope 8 at $DIR/combine_transmutes.rs:+8:9: +8:11 - let _17: u16; // in scope 8 at $DIR/combine_transmutes.rs:+9:9: +9:11 - scope 9 { - debug _a => _17; // in scope 9 at $DIR/combine_transmutes.rs:+9:9: +9:11 - let _19: u32; // in scope 9 at $DIR/combine_transmutes.rs:+10:9: +10:11 - scope 10 { - debug _a => _19; // in scope 10 at $DIR/combine_transmutes.rs:+10:9: +10:11 - let _21: i32; // in scope 10 at $DIR/combine_transmutes.rs:+11:9: +11:11 - scope 11 { - debug _a => _21; // in scope 11 at $DIR/combine_transmutes.rs:+11:9: +11:11 - let _23: std::mem::ManuallyDrop<std::string::String>; // in scope 11 at $DIR/combine_transmutes.rs:+12:9: +12:11 - scope 12 { - debug _a => _23; // in scope 12 at $DIR/combine_transmutes.rs:+12:9: +12:11 - } - } - } - } - } - } } } } @@ -66,93 +36,55 @@ bb0: { StorageLive(_1); // scope 0 at $DIR/combine_transmutes.rs:+1:9: +1:11 - StorageLive(_2); // scope 0 at $DIR/combine_transmutes.rs:+1:28: +1:41 - _2 = EnumNoRepr::A; // scope 0 at $DIR/combine_transmutes.rs:+1:28: +1:41 - _1 = move _2 as u8 (Transmute); // scope 0 at $DIR/combine_transmutes.rs:+1:18: +1:42 - StorageDead(_2); // scope 0 at $DIR/combine_transmutes.rs:+1:41: +1:42 + StorageLive(_2); // scope 0 at $DIR/combine_transmutes.rs:+1:28: +1:58 + _2 = Option::<NonZeroU8>::Some(const _); // scope 0 at $DIR/combine_transmutes.rs:+1:28: +1:58 + // mir::Constant + // + span: $DIR/combine_transmutes.rs:35:33: 35:57 + // + literal: Const { ty: NonZeroU8, val: Unevaluated(NonZeroU8::MAX, [], None) } + _1 = move _2 as u8 (Transmute); // scope 0 at $DIR/combine_transmutes.rs:+1:18: +1:59 + StorageDead(_2); // scope 0 at $DIR/combine_transmutes.rs:+1:58: +1:59 StorageLive(_3); // scope 1 at $DIR/combine_transmutes.rs:+2:9: +2:11 - StorageLive(_4); // scope 1 at $DIR/combine_transmutes.rs:+2:28: +2:41 - _4 = EnumNoRepr::B; // scope 1 at $DIR/combine_transmutes.rs:+2:28: +2:41 - _3 = move _4 as i8 (Transmute); // scope 1 at $DIR/combine_transmutes.rs:+2:18: +2:42 - StorageDead(_4); // scope 1 at $DIR/combine_transmutes.rs:+2:41: +2:42 + StorageLive(_4); // scope 1 at $DIR/combine_transmutes.rs:+2:29: +2:54 + _4 = Wrapping::<i16>(const 0_i16); // scope 1 at $DIR/combine_transmutes.rs:+2:29: +2:54 +- _3 = move _4 as i16 (Transmute); // scope 1 at $DIR/combine_transmutes.rs:+2:19: +2:55 ++ _3 = move (_4.0: i16); // scope 1 at $DIR/combine_transmutes.rs:+2:19: +2:55 + StorageDead(_4); // scope 1 at $DIR/combine_transmutes.rs:+2:54: +2:55 StorageLive(_5); // scope 2 at $DIR/combine_transmutes.rs:+3:9: +3:11 - StorageLive(_6); // scope 2 at $DIR/combine_transmutes.rs:+3:31: +3:47 - _6 = EnumReprIsize::A; // scope 2 at $DIR/combine_transmutes.rs:+3:31: +3:47 - _5 = move _6 as usize (Transmute); // scope 2 at $DIR/combine_transmutes.rs:+3:21: +3:48 - StorageDead(_6); // scope 2 at $DIR/combine_transmutes.rs:+3:47: +3:48 + StorageLive(_6); // scope 2 at $DIR/combine_transmutes.rs:+3:29: +3:54 + _6 = Wrapping::<i16>(const 0_i16); // scope 2 at $DIR/combine_transmutes.rs:+3:29: +3:54 + _5 = move _6 as u16 (Transmute); // scope 2 at $DIR/combine_transmutes.rs:+3:19: +3:55 + StorageDead(_6); // scope 2 at $DIR/combine_transmutes.rs:+3:54: +3:55 StorageLive(_7); // scope 3 at $DIR/combine_transmutes.rs:+4:9: +4:11 - StorageLive(_8); // scope 3 at $DIR/combine_transmutes.rs:+4:31: +4:47 - _8 = EnumReprIsize::B; // scope 3 at $DIR/combine_transmutes.rs:+4:31: +4:47 -- _7 = move _8 as isize (Transmute); // scope 3 at $DIR/combine_transmutes.rs:+4:21: +4:48 -+ _7 = discriminant(_8); // scope 3 at $DIR/combine_transmutes.rs:+4:21: +4:48 + StorageLive(_8); // scope 3 at $DIR/combine_transmutes.rs:+4:29: +4:47 + _8 = Union32 { u32: const 0_i32 }; // scope 3 at $DIR/combine_transmutes.rs:+4:29: +4:47 + _7 = move _8 as u32 (Transmute); // scope 3 at $DIR/combine_transmutes.rs:+4:19: +4:48 StorageDead(_8); // scope 3 at $DIR/combine_transmutes.rs:+4:47: +4:48 StorageLive(_9); // scope 4 at $DIR/combine_transmutes.rs:+5:9: +5:11 - StorageLive(_10); // scope 4 at $DIR/combine_transmutes.rs:+5:28: +5:52 - _10 = Less; // scope 4 at $DIR/combine_transmutes.rs:+5:28: +5:52 - _9 = move _10 as u8 (Transmute); // scope 4 at $DIR/combine_transmutes.rs:+5:18: +5:53 - StorageDead(_10); // scope 4 at $DIR/combine_transmutes.rs:+5:52: +5:53 + StorageLive(_10); // scope 4 at $DIR/combine_transmutes.rs:+5:29: +5:47 + _10 = Union32 { u32: const 0_u32 }; // scope 4 at $DIR/combine_transmutes.rs:+5:29: +5:47 + _9 = move _10 as i32 (Transmute); // scope 4 at $DIR/combine_transmutes.rs:+5:19: +5:48 + StorageDead(_10); // scope 4 at $DIR/combine_transmutes.rs:+5:47: +5:48 StorageLive(_11); // scope 5 at $DIR/combine_transmutes.rs:+6:9: +6:11 - StorageLive(_12); // scope 5 at $DIR/combine_transmutes.rs:+6:28: +6:52 - _12 = Less; // scope 5 at $DIR/combine_transmutes.rs:+6:28: +6:52 -- _11 = move _12 as i8 (Transmute); // scope 5 at $DIR/combine_transmutes.rs:+6:18: +6:53 -+ _11 = discriminant(_12); // scope 5 at $DIR/combine_transmutes.rs:+6:18: +6:53 - StorageDead(_12); // scope 5 at $DIR/combine_transmutes.rs:+6:52: +6:53 - StorageLive(_13); // scope 6 at $DIR/combine_transmutes.rs:+7:9: +7:11 - StorageLive(_14); // scope 6 at $DIR/combine_transmutes.rs:+7:28: +7:58 - _14 = Option::<NonZeroU8>::Some(const _); // scope 6 at $DIR/combine_transmutes.rs:+7:28: +7:58 - // mir::Constant - // + span: $DIR/combine_transmutes.rs:41:33: 41:57 - // + literal: Const { ty: NonZeroU8, val: Unevaluated(NonZeroU8::MAX, [], None) } - _13 = move _14 as u8 (Transmute); // scope 6 at $DIR/combine_transmutes.rs:+7:18: +7:59 - StorageDead(_14); // scope 6 at $DIR/combine_transmutes.rs:+7:58: +7:59 - StorageLive(_15); // scope 7 at $DIR/combine_transmutes.rs:+8:9: +8:11 - StorageLive(_16); // scope 7 at $DIR/combine_transmutes.rs:+8:29: +8:54 - _16 = Wrapping::<i16>(const 0_i16); // scope 7 at $DIR/combine_transmutes.rs:+8:29: +8:54 -- _15 = move _16 as i16 (Transmute); // scope 7 at $DIR/combine_transmutes.rs:+8:19: +8:55 -+ _15 = move (_16.0: i16); // scope 7 at $DIR/combine_transmutes.rs:+8:19: +8:55 - StorageDead(_16); // scope 7 at $DIR/combine_transmutes.rs:+8:54: +8:55 - StorageLive(_17); // scope 8 at $DIR/combine_transmutes.rs:+9:9: +9:11 - StorageLive(_18); // scope 8 at $DIR/combine_transmutes.rs:+9:29: +9:54 - _18 = Wrapping::<i16>(const 0_i16); // scope 8 at $DIR/combine_transmutes.rs:+9:29: +9:54 - _17 = move _18 as u16 (Transmute); // scope 8 at $DIR/combine_transmutes.rs:+9:19: +9:55 - StorageDead(_18); // scope 8 at $DIR/combine_transmutes.rs:+9:54: +9:55 - StorageLive(_19); // scope 9 at $DIR/combine_transmutes.rs:+10:9: +10:11 - StorageLive(_20); // scope 9 at $DIR/combine_transmutes.rs:+10:29: +10:47 - _20 = Union32 { u32: const 0_i32 }; // scope 9 at $DIR/combine_transmutes.rs:+10:29: +10:47 - _19 = move _20 as u32 (Transmute); // scope 9 at $DIR/combine_transmutes.rs:+10:19: +10:48 - StorageDead(_20); // scope 9 at $DIR/combine_transmutes.rs:+10:47: +10:48 - StorageLive(_21); // scope 10 at $DIR/combine_transmutes.rs:+11:9: +11:11 - StorageLive(_22); // scope 10 at $DIR/combine_transmutes.rs:+11:29: +11:47 - _22 = Union32 { u32: const 0_u32 }; // scope 10 at $DIR/combine_transmutes.rs:+11:29: +11:47 - _21 = move _22 as i32 (Transmute); // scope 10 at $DIR/combine_transmutes.rs:+11:19: +11:48 - StorageDead(_22); // scope 10 at $DIR/combine_transmutes.rs:+11:47: +11:48 - StorageLive(_23); // scope 11 at $DIR/combine_transmutes.rs:+12:9: +12:11 - StorageLive(_24); // scope 11 at $DIR/combine_transmutes.rs:+12:46: +12:77 - _24 = MaybeUninit::<String>::uninit() -> [return: bb1, unwind unreachable]; // scope 11 at $DIR/combine_transmutes.rs:+12:46: +12:77 + StorageLive(_12); // scope 5 at $DIR/combine_transmutes.rs:+6:46: +6:77 + _12 = MaybeUninit::<String>::uninit() -> [return: bb1, unwind unreachable]; // scope 5 at $DIR/combine_transmutes.rs:+6:46: +6:77 // mir::Constant - // + span: $DIR/combine_transmutes.rs:46:46: 46:75 - // + user_ty: UserType(23) + // + span: $DIR/combine_transmutes.rs:40:46: 40:75 + // + user_ty: UserType(11) // + literal: Const { ty: fn() -> MaybeUninit<String> {MaybeUninit::<String>::uninit}, val: Value(<ZST>) } } bb1: { -- _23 = move _24 as std::mem::ManuallyDrop<std::string::String> (Transmute); // scope 11 at $DIR/combine_transmutes.rs:+12:36: +12:78 -+ _23 = move (_24.1: std::mem::ManuallyDrop<std::string::String>); // scope 11 at $DIR/combine_transmutes.rs:+12:36: +12:78 - StorageDead(_24); // scope 11 at $DIR/combine_transmutes.rs:+12:77: +12:78 - _0 = const (); // scope 0 at $DIR/combine_transmutes.rs:+0:32: +13:2 - StorageDead(_23); // scope 11 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_21); // scope 10 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_19); // scope 9 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_17); // scope 8 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_15); // scope 7 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_13); // scope 6 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_11); // scope 5 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_9); // scope 4 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_7); // scope 3 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_5); // scope 2 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_3); // scope 1 at $DIR/combine_transmutes.rs:+13:1: +13:2 - StorageDead(_1); // scope 0 at $DIR/combine_transmutes.rs:+13:1: +13:2 - return; // scope 0 at $DIR/combine_transmutes.rs:+13:2: +13:2 +- _11 = move _12 as std::mem::ManuallyDrop<std::string::String> (Transmute); // scope 5 at $DIR/combine_transmutes.rs:+6:36: +6:78 ++ _11 = move (_12.1: std::mem::ManuallyDrop<std::string::String>); // scope 5 at $DIR/combine_transmutes.rs:+6:36: +6:78 + StorageDead(_12); // scope 5 at $DIR/combine_transmutes.rs:+6:77: +6:78 + _0 = const (); // scope 0 at $DIR/combine_transmutes.rs:+0:32: +7:2 + StorageDead(_11); // scope 5 at $DIR/combine_transmutes.rs:+7:1: +7:2 + StorageDead(_9); // scope 4 at $DIR/combine_transmutes.rs:+7:1: +7:2 + StorageDead(_7); // scope 3 at $DIR/combine_transmutes.rs:+7:1: +7:2 + StorageDead(_5); // scope 2 at $DIR/combine_transmutes.rs:+7:1: +7:2 + StorageDead(_3); // scope 1 at $DIR/combine_transmutes.rs:+7:1: +7:2 + StorageDead(_1); // scope 0 at $DIR/combine_transmutes.rs:+7:1: +7:2 + return; // scope 0 at $DIR/combine_transmutes.rs:+7:2: +7:2 } } diff --git a/tests/mir-opt/combine_transmutes.rs b/tests/mir-opt/combine_transmutes.rs index 7088488c1b8..403f9356ce2 100644 --- a/tests/mir-opt/combine_transmutes.rs +++ b/tests/mir-opt/combine_transmutes.rs @@ -32,12 +32,6 @@ pub unsafe fn integer_transmutes() { // EMIT_MIR combine_transmutes.adt_transmutes.InstSimplify.diff pub unsafe fn adt_transmutes() { - let _a: u8 = transmute(EnumNoRepr::A); - let _a: i8 = transmute(EnumNoRepr::B); - let _a: usize = transmute(EnumReprIsize::A); - let _a: isize = transmute(EnumReprIsize::B); - let _a: u8 = transmute(std::cmp::Ordering::Less); - let _a: i8 = transmute(std::cmp::Ordering::Less); let _a: u8 = transmute(Some(std::num::NonZeroU8::MAX)); let _a: i16 = transmute(std::num::Wrapping(0_i16)); let _a: u16 = transmute(std::num::Wrapping(0_i16)); @@ -46,20 +40,4 @@ pub unsafe fn adt_transmutes() { let _a: ManuallyDrop<String> = transmute(MaybeUninit::<String>::uninit()); } -#[inline(always)] -#[custom_mir(dialect = "runtime", phase = "initial")] -const unsafe fn mir_transmute<T, U>(x: T) -> U { - mir!{ - { - RET = CastTransmute(x); - Return() - } - } -} - -pub enum EnumNoRepr { A, B, C } - -#[repr(isize)] -pub enum EnumReprIsize { A, B, C } - pub union Union32 { u32: u32, i32: i32 } |