diff --git a/compiler/rustc_mir_transform/src/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs index cb134a20ea03e..4a9bd9df327f5 100644 --- a/compiler/rustc_mir_transform/src/const_prop.rs +++ b/compiler/rustc_mir_transform/src/const_prop.rs @@ -1066,32 +1066,32 @@ impl<'tcx> MutVisitor<'tcx> for ConstPropagator<'_, 'tcx> { let source_info = terminator.source_info; self.source_info = Some(source_info); self.super_terminator(terminator, location); + // Do NOT early return in this function, it does some crucial fixup of the state at the end! match &mut terminator.kind { TerminatorKind::Assert { expected, ref mut cond, .. } => { if let Some(ref value) = self.eval_operand(&cond) { trace!("assertion on {:?} should be {:?}", value, expected); let expected = Scalar::from_bool(*expected); - let Ok(value_const) = self.ecx.read_scalar(&value) else { - // FIXME should be used use_ecx rather than a local match... but we have - // quite a few of these read_scalar/read_immediate that need fixing. - return - }; - if expected != value_const { - // Poison all places this operand references so that further code - // doesn't use the invalid value - match cond { - Operand::Move(ref place) | Operand::Copy(ref place) => { - Self::remove_const(&mut self.ecx, place.local); + // FIXME should be used use_ecx rather than a local match... but we have + // quite a few of these read_scalar/read_immediate that need fixing. + if let Ok(value_const) = self.ecx.read_scalar(&value) { + if expected != value_const { + // Poison all places this operand references so that further code + // doesn't use the invalid value + match cond { + Operand::Move(ref place) | Operand::Copy(ref place) => { + Self::remove_const(&mut self.ecx, place.local); + } + Operand::Constant(_) => {} + } + } else { + if self.should_const_prop(value) { + *cond = self.operand_from_scalar( + value_const, + self.tcx.types.bool, + source_info.span, + ); } - Operand::Constant(_) => {} - } - } else { - if self.should_const_prop(value) { - *cond = self.operand_from_scalar( - value_const, - self.tcx.types.bool, - source_info.span, - ); } } } diff --git a/src/test/mir-opt/issue-101973.rs b/src/test/mir-opt/issue-101973.rs new file mode 100644 index 0000000000000..216659a235ef7 --- /dev/null +++ b/src/test/mir-opt/issue-101973.rs @@ -0,0 +1,20 @@ +// compile-flags: -O -C debug-assertions=on +// This needs inlining followed by ConstProp to reproduce, so we cannot use "unit-test". + +#[inline] +pub fn imm8(x: u32) -> u32 { + let mut out = 0u32; + out |= (x >> 0) & 0xff; + out +} + +// EMIT_MIR issue_101973.inner.ConstProp.diff +#[inline(never)] +pub fn inner(fields: u32) -> i64 { + imm8(fields).rotate_right(((fields >> 8) & 0xf) << 1) as i32 as i64 +} + +fn main() { + let val = inner(0xe32cf20f); + assert_eq!(val as u64, 0xfffffffff0000000); +} diff --git a/src/test/mir-opt/issue_101973.inner.ConstProp.diff b/src/test/mir-opt/issue_101973.inner.ConstProp.diff new file mode 100644 index 0000000000000..89733a9a2cb7c --- /dev/null +++ b/src/test/mir-opt/issue_101973.inner.ConstProp.diff @@ -0,0 +1,100 @@ +- // MIR for `inner` before ConstProp ++ // MIR for `inner` after ConstProp + + fn inner(_1: u32) -> i64 { + debug fields => _1; // in scope 0 at $DIR/issue-101973.rs:+0:14: +0:20 + let mut _0: i64; // return place in scope 0 at $DIR/issue-101973.rs:+0:30: +0:33 + let mut _2: i32; // in scope 0 at $DIR/issue-101973.rs:+1:5: +1:65 + let mut _3: u32; // in scope 0 at $DIR/issue-101973.rs:+1:5: +1:58 + let mut _4: u32; // in scope 0 at $DIR/issue-101973.rs:+1:5: +1:17 + let mut _5: u32; // in scope 0 at $DIR/issue-101973.rs:+1:10: +1:16 + let mut _6: u32; // in scope 0 at $DIR/issue-101973.rs:+1:31: +1:57 + let mut _7: u32; // in scope 0 at $DIR/issue-101973.rs:+1:31: +1:52 + let mut _8: u32; // in scope 0 at $DIR/issue-101973.rs:+1:32: +1:45 + let mut _9: u32; // in scope 0 at $DIR/issue-101973.rs:+1:33: +1:39 + let mut _10: (u32, bool); // in scope 0 at $DIR/issue-101973.rs:+1:32: +1:45 + let mut _11: (u32, bool); // in scope 0 at $DIR/issue-101973.rs:+1:31: +1:57 + scope 1 (inlined imm8) { // at $DIR/issue-101973.rs:14:5: 14:17 + debug x => _5; // in scope 1 at $DIR/issue-101973.rs:5:13: 5:14 + let mut _12: u32; // in scope 1 at $DIR/issue-101973.rs:7:12: 7:27 + let mut _13: u32; // in scope 1 at $DIR/issue-101973.rs:7:12: 7:20 + let mut _14: u32; // in scope 1 at $DIR/issue-101973.rs:7:13: 7:14 + let mut _15: (u32, bool); // in scope 1 at $DIR/issue-101973.rs:7:12: 7:20 + scope 2 { + debug out => _4; // in scope 2 at $DIR/issue-101973.rs:6:9: 6:16 + } + } + scope 3 (inlined core::num::::rotate_right) { // at $DIR/issue-101973.rs:14:5: 14:58 + debug self => _4; // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + debug n => _6; // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + let mut _16: u32; // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + let mut _17: u32; // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + } + + bb0: { + StorageLive(_2); // scope 0 at $DIR/issue-101973.rs:+1:5: +1:65 + StorageLive(_3); // scope 0 at $DIR/issue-101973.rs:+1:5: +1:58 + StorageLive(_4); // scope 0 at $DIR/issue-101973.rs:+1:5: +1:17 + StorageLive(_5); // scope 0 at $DIR/issue-101973.rs:+1:10: +1:16 + _5 = _1; // scope 0 at $DIR/issue-101973.rs:+1:10: +1:16 + _4 = const 0_u32; // scope 1 at $DIR/issue-101973.rs:6:19: 6:23 + StorageLive(_12); // scope 2 at $DIR/issue-101973.rs:7:12: 7:27 + StorageLive(_13); // scope 2 at $DIR/issue-101973.rs:7:12: 7:20 + StorageLive(_14); // scope 2 at $DIR/issue-101973.rs:7:13: 7:14 + _14 = _5; // scope 2 at $DIR/issue-101973.rs:7:13: 7:14 + _15 = CheckedShr(_14, const 0_i32); // scope 2 at $DIR/issue-101973.rs:7:12: 7:20 + assert(!move (_15.1: bool), "attempt to shift right by `{}`, which would overflow", const 0_i32) -> bb3; // scope 2 at $DIR/issue-101973.rs:7:12: 7:20 + } + + bb1: { + _8 = move (_10.0: u32); // scope 0 at $DIR/issue-101973.rs:+1:32: +1:45 + StorageDead(_9); // scope 0 at $DIR/issue-101973.rs:+1:44: +1:45 + _7 = BitAnd(move _8, const 15_u32); // scope 0 at $DIR/issue-101973.rs:+1:31: +1:52 + StorageDead(_8); // scope 0 at $DIR/issue-101973.rs:+1:51: +1:52 + _11 = CheckedShl(_7, const 1_i32); // scope 0 at $DIR/issue-101973.rs:+1:31: +1:57 + assert(!move (_11.1: bool), "attempt to shift left by `{}`, which would overflow", const 1_i32) -> bb2; // scope 0 at $DIR/issue-101973.rs:+1:31: +1:57 + } + + bb2: { + _6 = move (_11.0: u32); // scope 0 at $DIR/issue-101973.rs:+1:31: +1:57 + StorageDead(_7); // scope 0 at $DIR/issue-101973.rs:+1:56: +1:57 + StorageLive(_16); // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + _16 = _4; // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + StorageLive(_17); // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + _17 = _6; // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + _3 = rotate_right::(move _16, move _17) -> bb4; // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + // mir::Constant + // + span: $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + // + literal: Const { ty: extern "rust-intrinsic" fn(u32, u32) -> u32 {rotate_right::}, val: Value() } + } + + bb3: { + _13 = move (_15.0: u32); // scope 2 at $DIR/issue-101973.rs:7:12: 7:20 + StorageDead(_14); // scope 2 at $DIR/issue-101973.rs:7:19: 7:20 + _12 = BitAnd(move _13, const 255_u32); // scope 2 at $DIR/issue-101973.rs:7:12: 7:27 + StorageDead(_13); // scope 2 at $DIR/issue-101973.rs:7:26: 7:27 + _4 = BitOr(_4, move _12); // scope 2 at $DIR/issue-101973.rs:7:5: 7:27 + StorageDead(_12); // scope 2 at $DIR/issue-101973.rs:7:26: 7:27 + StorageDead(_5); // scope 0 at $DIR/issue-101973.rs:+1:16: +1:17 + StorageLive(_6); // scope 0 at $DIR/issue-101973.rs:+1:31: +1:57 + StorageLive(_7); // scope 0 at $DIR/issue-101973.rs:+1:31: +1:52 + StorageLive(_8); // scope 0 at $DIR/issue-101973.rs:+1:32: +1:45 + StorageLive(_9); // scope 0 at $DIR/issue-101973.rs:+1:33: +1:39 + _9 = _1; // scope 0 at $DIR/issue-101973.rs:+1:33: +1:39 + _10 = CheckedShr(_9, const 8_i32); // scope 0 at $DIR/issue-101973.rs:+1:32: +1:45 + assert(!move (_10.1: bool), "attempt to shift right by `{}`, which would overflow", const 8_i32) -> bb1; // scope 0 at $DIR/issue-101973.rs:+1:32: +1:45 + } + + bb4: { + StorageDead(_17); // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + StorageDead(_16); // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL + StorageDead(_6); // scope 0 at $DIR/issue-101973.rs:+1:57: +1:58 + StorageDead(_4); // scope 0 at $DIR/issue-101973.rs:+1:57: +1:58 + _2 = move _3 as i32 (Misc); // scope 0 at $DIR/issue-101973.rs:+1:5: +1:65 + StorageDead(_3); // scope 0 at $DIR/issue-101973.rs:+1:64: +1:65 + _0 = move _2 as i64 (Misc); // scope 0 at $DIR/issue-101973.rs:+1:5: +1:72 + StorageDead(_2); // scope 0 at $DIR/issue-101973.rs:+1:71: +1:72 + return; // scope 0 at $DIR/issue-101973.rs:+2:2: +2:2 + } + } +