From 9b846d4637f10a64f89c80631eae7710c23f1a5e Mon Sep 17 00:00:00 2001 From: Camille GILLOT Date: Fri, 5 Jan 2024 21:52:58 +0000 Subject: [PATCH] Dereference immutable borrows in GVN. --- compiler/rustc_mir_transform/src/gvn.rs | 16 ++++++++ tests/coverage/issue-83601.cov-map | 6 +-- tests/coverage/issue-84561.cov-map | 22 +++++------ .../mir-opt/gvn.borrowed.GVN.panic-abort.diff | 3 +- .../gvn.borrowed.GVN.panic-unwind.diff | 3 +- tests/mir-opt/gvn.rs | 2 +- tests/mir-opt/gvn.slices.GVN.panic-abort.diff | 38 ++++++++++++------- .../mir-opt/gvn.slices.GVN.panic-unwind.diff | 38 ++++++++++++------- .../gvn_uninhabited.f.GVN.panic-abort.diff | 3 +- .../gvn_uninhabited.f.GVN.panic-unwind.diff | 3 +- 10 files changed, 87 insertions(+), 47 deletions(-) diff --git a/compiler/rustc_mir_transform/src/gvn.rs b/compiler/rustc_mir_transform/src/gvn.rs index 04251978865..637a2fbed18 100644 --- a/compiler/rustc_mir_transform/src/gvn.rs +++ b/compiler/rustc_mir_transform/src/gvn.rs @@ -724,6 +724,14 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { // Invariant: `value` holds the value up-to the `index`th projection excluded. let mut value = self.locals[place.local]?; for (index, proj) in place.projection.iter().enumerate() { + if let Value::Projection(pointer, ProjectionElem::Deref) = *self.get(value) + && let Value::Address { place: mut pointee, kind, .. } = *self.get(pointer) + && let AddressKind::Ref(BorrowKind::Shared) = kind + && let Some(v) = self.simplify_place_value(&mut pointee, location) + { + value = v; + place_ref = pointee.project_deeper(&place.projection[index..], self.tcx).as_ref(); + } if let Some(local) = self.try_as_local(value, location) { // Both `local` and `Place { local: place.local, projection: projection[..index] }` // hold the same value. Therefore, following place holds the value in the original @@ -735,6 +743,14 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { value = self.project(base, value, proj)?; } + if let Value::Projection(pointer, ProjectionElem::Deref) = *self.get(value) + && let Value::Address { place: mut pointee, kind, .. } = *self.get(pointer) + && let AddressKind::Ref(BorrowKind::Shared) = kind + && let Some(v) = self.simplify_place_value(&mut pointee, location) + { + value = v; + place_ref = pointee.project_deeper(&[], self.tcx).as_ref(); + } if let Some(new_local) = self.try_as_local(value, location) { place_ref = PlaceRef { local: new_local, projection: &[] }; } diff --git a/tests/coverage/issue-83601.cov-map b/tests/coverage/issue-83601.cov-map index f2447e3c92c..ddb4407881a 100644 --- a/tests/coverage/issue-83601.cov-map +++ b/tests/coverage/issue-83601.cov-map @@ -1,12 +1,12 @@ Function name: issue_83601::main -Raw bytes (21): 0x[01, 01, 01, 05, 09, 03, 01, 06, 01, 02, 1c, 05, 03, 09, 01, 1c, 02, 02, 05, 03, 02] +Raw bytes (21): 0x[01, 01, 01, 05, 00, 03, 01, 06, 01, 02, 1c, 05, 03, 09, 01, 1c, 02, 02, 05, 03, 02] Number of files: 1 - file 0 => global file 1 Number of expressions: 1 -- expression 0 operands: lhs = Counter(1), rhs = Counter(2) +- expression 0 operands: lhs = Counter(1), rhs = Zero Number of file 0 mappings: 3 - Code(Counter(0)) at (prev + 6, 1) to (start + 2, 28) - Code(Counter(1)) at (prev + 3, 9) to (start + 1, 28) - Code(Expression(0, Sub)) at (prev + 2, 5) to (start + 3, 2) - = (c1 - c2) + = (c1 - Zero) diff --git a/tests/coverage/issue-84561.cov-map b/tests/coverage/issue-84561.cov-map index a81884ea942..ab66a2fffce 100644 --- a/tests/coverage/issue-84561.cov-map +++ b/tests/coverage/issue-84561.cov-map @@ -77,22 +77,22 @@ Number of file 0 mappings: 1 - Code(Counter(0)) at (prev + 167, 9) to (start + 2, 10) Function name: issue_84561::test3 -Raw bytes (436): 0x[01, 01, 41, 05, 09, 0d, 00, 15, 19, 12, 00, 15, 19, 21, 00, 1e, 00, 21, 00, 31, 00, 3d, 41, 2e, 45, 3d, 41, 42, 49, 45, 00, 3f, 51, 42, 49, 45, 00, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 92, 01, 55, 51, 00, 8f, 01, 5d, 92, 01, 55, 51, 00, 87, 01, 61, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 82, 01, 65, 87, 01, 61, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, 00, fe, 01, 82, 02, 00, 69, 6d, 69, 6d, 82, 02, 00, 69, 6d, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, f3, 01, 7d, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, ee, 01, 00, f3, 01, 7d, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, 33, 01, 08, 01, 03, 1c, 05, 04, 09, 01, 1c, 02, 02, 05, 04, 1f, 0d, 05, 05, 00, 1f, 06, 01, 05, 00, 1f, 15, 01, 09, 01, 1c, 12, 02, 05, 00, 1f, 0e, 01, 05, 00, 0f, 00, 00, 20, 00, 30, 21, 01, 05, 03, 0f, 00, 03, 20, 00, 30, 00, 00, 33, 00, 41, 00, 00, 4b, 00, 5a, 1e, 01, 05, 00, 0f, 00, 05, 09, 03, 10, 00, 05, 0d, 00, 1b, 00, 02, 0d, 00, 1c, 1a, 04, 09, 05, 06, 31, 06, 05, 03, 06, 22, 04, 05, 03, 06, 3d, 04, 09, 04, 06, 2e, 05, 08, 00, 0f, 45, 01, 09, 03, 0a, 2a, 05, 09, 03, 0a, 3f, 05, 08, 00, 0f, 51, 01, 09, 00, 13, 00, 03, 0d, 00, 1d, 3a, 03, 09, 00, 13, 00, 03, 0d, 00, 1d, 87, 01, 03, 05, 00, 0f, 8f, 01, 01, 0c, 00, 13, 5d, 01, 0d, 00, 13, 8a, 01, 02, 0d, 00, 13, 82, 01, 04, 05, 02, 13, 65, 03, 0d, 00, 13, 7e, 02, 0d, 00, 13, f3, 01, 03, 05, 00, 0f, 69, 01, 0c, 00, 13, 6d, 01, 0d, 03, 0e, 75, 04, 0d, 00, 13, fb, 01, 02, 0d, 00, 17, 82, 02, 01, 14, 00, 1b, 00, 01, 15, 00, 1b, fe, 01, 02, 15, 00, 1b, f6, 01, 04, 0d, 00, 13, 7d, 03, 09, 00, 19, ee, 01, 02, 05, 00, 0f, ea, 01, 03, 09, 00, 22, 00, 02, 05, 00, 0f, 00, 03, 09, 00, 2c, 00, 02, 01, 00, 02] +Raw bytes (436): 0x[01, 01, 41, 05, 00, 0d, 00, 15, 00, 12, 00, 15, 00, 21, 00, 1e, 00, 21, 00, 31, 00, 3d, 00, 2e, 45, 3d, 00, 42, 49, 45, 00, 3f, 51, 42, 49, 45, 00, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 92, 01, 55, 51, 00, 8f, 01, 5d, 92, 01, 55, 51, 00, 87, 01, 61, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 82, 01, 65, 87, 01, 61, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, 00, fe, 01, 82, 02, 00, 69, 6d, 69, 6d, 82, 02, 00, 69, 6d, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, f3, 01, 7d, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, ee, 01, 00, f3, 01, 7d, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, 33, 01, 08, 01, 03, 1c, 05, 04, 09, 01, 1c, 02, 02, 05, 04, 1f, 0d, 05, 05, 00, 1f, 06, 01, 05, 00, 1f, 15, 01, 09, 01, 1c, 12, 02, 05, 00, 1f, 0e, 01, 05, 00, 0f, 00, 00, 20, 00, 30, 21, 01, 05, 03, 0f, 00, 03, 20, 00, 30, 00, 00, 33, 00, 41, 00, 00, 4b, 00, 5a, 1e, 01, 05, 00, 0f, 00, 05, 09, 03, 10, 00, 05, 0d, 00, 1b, 00, 02, 0d, 00, 1c, 1a, 04, 09, 05, 06, 31, 06, 05, 03, 06, 22, 04, 05, 03, 06, 3d, 04, 09, 04, 06, 2e, 05, 08, 00, 0f, 45, 01, 09, 03, 0a, 2a, 05, 09, 03, 0a, 3f, 05, 08, 00, 0f, 51, 01, 09, 00, 13, 00, 03, 0d, 00, 1d, 3a, 03, 09, 00, 13, 00, 03, 0d, 00, 1d, 87, 01, 03, 05, 00, 0f, 8f, 01, 01, 0c, 00, 13, 5d, 01, 0d, 00, 13, 8a, 01, 02, 0d, 00, 13, 82, 01, 04, 05, 02, 13, 65, 03, 0d, 00, 13, 7e, 02, 0d, 00, 13, f3, 01, 03, 05, 00, 0f, 69, 01, 0c, 00, 13, 6d, 01, 0d, 03, 0e, 75, 04, 0d, 00, 13, fb, 01, 02, 0d, 00, 17, 82, 02, 01, 14, 00, 1b, 00, 01, 15, 00, 1b, fe, 01, 02, 15, 00, 1b, f6, 01, 04, 0d, 00, 13, 7d, 03, 09, 00, 19, ee, 01, 02, 05, 00, 0f, ea, 01, 03, 09, 00, 22, 00, 02, 05, 00, 0f, 00, 03, 09, 00, 2c, 00, 02, 01, 00, 02] Number of files: 1 - file 0 => global file 1 Number of expressions: 65 -- expression 0 operands: lhs = Counter(1), rhs = Counter(2) +- expression 0 operands: lhs = Counter(1), rhs = Zero - expression 1 operands: lhs = Counter(3), rhs = Zero -- expression 2 operands: lhs = Counter(5), rhs = Counter(6) +- expression 2 operands: lhs = Counter(5), rhs = Zero - expression 3 operands: lhs = Expression(4, Sub), rhs = Zero -- expression 4 operands: lhs = Counter(5), rhs = Counter(6) +- expression 4 operands: lhs = Counter(5), rhs = Zero - expression 5 operands: lhs = Counter(8), rhs = Zero - expression 6 operands: lhs = Expression(7, Sub), rhs = Zero - expression 7 operands: lhs = Counter(8), rhs = Zero - expression 8 operands: lhs = Counter(12), rhs = Zero -- expression 9 operands: lhs = Counter(15), rhs = Counter(16) +- expression 9 operands: lhs = Counter(15), rhs = Zero - expression 10 operands: lhs = Expression(11, Sub), rhs = Counter(17) -- expression 11 operands: lhs = Counter(15), rhs = Counter(16) +- expression 11 operands: lhs = Counter(15), rhs = Zero - expression 12 operands: lhs = Expression(16, Sub), rhs = Counter(18) - expression 13 operands: lhs = Counter(17), rhs = Zero - expression 14 operands: lhs = Expression(15, Add), rhs = Counter(20) @@ -150,15 +150,15 @@ Number of file 0 mappings: 51 - Code(Counter(0)) at (prev + 8, 1) to (start + 3, 28) - Code(Counter(1)) at (prev + 4, 9) to (start + 1, 28) - Code(Expression(0, Sub)) at (prev + 2, 5) to (start + 4, 31) - = (c1 - c2) + = (c1 - Zero) - Code(Counter(3)) at (prev + 5, 5) to (start + 0, 31) - Code(Expression(1, Sub)) at (prev + 1, 5) to (start + 0, 31) = (c3 - Zero) - Code(Counter(5)) at (prev + 1, 9) to (start + 1, 28) - Code(Expression(4, Sub)) at (prev + 2, 5) to (start + 0, 31) - = (c5 - c6) + = (c5 - Zero) - Code(Expression(3, Sub)) at (prev + 1, 5) to (start + 0, 15) - = ((c5 - c6) - Zero) + = ((c5 - Zero) - Zero) - Code(Zero) at (prev + 0, 32) to (start + 0, 48) - Code(Counter(8)) at (prev + 1, 5) to (start + 3, 15) - Code(Zero) at (prev + 3, 32) to (start + 0, 48) @@ -176,10 +176,10 @@ Number of file 0 mappings: 51 = (c12 - Zero) - Code(Counter(15)) at (prev + 4, 9) to (start + 4, 6) - Code(Expression(11, Sub)) at (prev + 5, 8) to (start + 0, 15) - = (c15 - c16) + = (c15 - Zero) - Code(Counter(17)) at (prev + 1, 9) to (start + 3, 10) - Code(Expression(10, Sub)) at (prev + 5, 9) to (start + 3, 10) - = ((c15 - c16) - c17) + = ((c15 - Zero) - c17) - Code(Expression(15, Add)) at (prev + 5, 8) to (start + 0, 15) = ((c17 - Zero) + c18) - Code(Counter(20)) at (prev + 1, 9) to (start + 0, 19) diff --git a/tests/mir-opt/gvn.borrowed.GVN.panic-abort.diff b/tests/mir-opt/gvn.borrowed.GVN.panic-abort.diff index df3291bc1b5..e0e3136a498 100644 --- a/tests/mir-opt/gvn.borrowed.GVN.panic-abort.diff +++ b/tests/mir-opt/gvn.borrowed.GVN.panic-abort.diff @@ -18,7 +18,8 @@ } bb2: { - _0 = opaque::((*_3)) -> [return: bb3, unwind unreachable]; +- _0 = opaque::((*_3)) -> [return: bb3, unwind unreachable]; ++ _0 = opaque::(_1) -> [return: bb3, unwind unreachable]; } bb3: { diff --git a/tests/mir-opt/gvn.borrowed.GVN.panic-unwind.diff b/tests/mir-opt/gvn.borrowed.GVN.panic-unwind.diff index 8f670de61ee..e60e1b22c9a 100644 --- a/tests/mir-opt/gvn.borrowed.GVN.panic-unwind.diff +++ b/tests/mir-opt/gvn.borrowed.GVN.panic-unwind.diff @@ -18,7 +18,8 @@ } bb2: { - _0 = opaque::((*_3)) -> [return: bb3, unwind continue]; +- _0 = opaque::((*_3)) -> [return: bb3, unwind continue]; ++ _0 = opaque::(_1) -> [return: bb3, unwind continue]; } bb3: { diff --git a/tests/mir-opt/gvn.rs b/tests/mir-opt/gvn.rs index f168d4fec89..8c2d4db642d 100644 --- a/tests/mir-opt/gvn.rs +++ b/tests/mir-opt/gvn.rs @@ -730,7 +730,7 @@ fn borrowed(x: u32) { // CHECK: bb1: { // CHECK-NEXT: _0 = opaque::(_1) // CHECK: bb2: { - // CHECK-NEXT: _0 = opaque::((*_3)) + // CHECK-NEXT: _0 = opaque::(_1) mir!( { let a = x; diff --git a/tests/mir-opt/gvn.slices.GVN.panic-abort.diff b/tests/mir-opt/gvn.slices.GVN.panic-abort.diff index 2389d98b5b3..fb67e3d5994 100644 --- a/tests/mir-opt/gvn.slices.GVN.panic-abort.diff +++ b/tests/mir-opt/gvn.slices.GVN.panic-abort.diff @@ -111,8 +111,9 @@ StorageLive(_7); StorageLive(_8); - StorageLive(_9); +- StorageLive(_10); ++ nop; + nop; - StorageLive(_10); StorageLive(_11); _11 = &(*_1); _10 = core::str::::as_ptr(move _11) -> [return: bb3, unwind unreachable]; @@ -122,8 +123,9 @@ StorageDead(_11); _9 = &_10; - StorageLive(_12); +- StorageLive(_13); ++ nop; + nop; - StorageLive(_13); StorageLive(_14); - _14 = &(*_4); + _14 = &(*_1); @@ -148,11 +150,12 @@ StorageLive(_17); StorageLive(_18); - _18 = (*_15); -+ _18 = (*_9); ++ _18 = _10; StorageLive(_19); - _19 = (*_16); -+ _19 = (*_12); - _17 = Eq(move _18, move _19); +- _17 = Eq(move _18, move _19); ++ _19 = _13; ++ _17 = Eq(_10, _13); switchInt(move _17) -> [0: bb6, otherwise: bb5]; } @@ -163,8 +166,10 @@ StorageDead(_17); StorageDead(_16); StorageDead(_15); - StorageDead(_13); - StorageDead(_10); +- StorageDead(_13); +- StorageDead(_10); ++ nop; ++ nop; StorageDead(_8); StorageDead(_7); - StorageLive(_29); @@ -213,8 +218,9 @@ StorageLive(_33); StorageLive(_34); - StorageLive(_35); +- StorageLive(_36); ++ nop; + nop; - StorageLive(_36); StorageLive(_37); _37 = &(*_1); _36 = core::str::::as_ptr(move _37) -> [return: bb8, unwind unreachable]; @@ -224,8 +230,9 @@ StorageDead(_37); _35 = &_36; - StorageLive(_38); +- StorageLive(_39); ++ nop; + nop; - StorageLive(_39); StorageLive(_40); _40 = &(*_29); _39 = core::slice::::as_ptr(move _40) -> [return: bb9, unwind unreachable]; @@ -249,11 +256,12 @@ StorageLive(_43); StorageLive(_44); - _44 = (*_41); -+ _44 = (*_35); ++ _44 = _36; StorageLive(_45); - _45 = (*_42); -+ _45 = (*_38); - _43 = Eq(move _44, move _45); +- _43 = Eq(move _44, move _45); ++ _45 = _39; ++ _43 = Eq(_36, _39); switchInt(move _43) -> [0: bb11, otherwise: bb10]; } @@ -264,8 +272,10 @@ StorageDead(_43); StorageDead(_42); StorageDead(_41); - StorageDead(_39); - StorageDead(_36); +- StorageDead(_39); +- StorageDead(_36); ++ nop; ++ nop; StorageDead(_34); StorageDead(_33); _0 = const (); diff --git a/tests/mir-opt/gvn.slices.GVN.panic-unwind.diff b/tests/mir-opt/gvn.slices.GVN.panic-unwind.diff index 50715d748e7..ae3013b011e 100644 --- a/tests/mir-opt/gvn.slices.GVN.panic-unwind.diff +++ b/tests/mir-opt/gvn.slices.GVN.panic-unwind.diff @@ -111,8 +111,9 @@ StorageLive(_7); StorageLive(_8); - StorageLive(_9); +- StorageLive(_10); ++ nop; + nop; - StorageLive(_10); StorageLive(_11); _11 = &(*_1); _10 = core::str::::as_ptr(move _11) -> [return: bb3, unwind continue]; @@ -122,8 +123,9 @@ StorageDead(_11); _9 = &_10; - StorageLive(_12); +- StorageLive(_13); ++ nop; + nop; - StorageLive(_13); StorageLive(_14); - _14 = &(*_4); + _14 = &(*_1); @@ -148,11 +150,12 @@ StorageLive(_17); StorageLive(_18); - _18 = (*_15); -+ _18 = (*_9); ++ _18 = _10; StorageLive(_19); - _19 = (*_16); -+ _19 = (*_12); - _17 = Eq(move _18, move _19); +- _17 = Eq(move _18, move _19); ++ _19 = _13; ++ _17 = Eq(_10, _13); switchInt(move _17) -> [0: bb6, otherwise: bb5]; } @@ -163,8 +166,10 @@ StorageDead(_17); StorageDead(_16); StorageDead(_15); - StorageDead(_13); - StorageDead(_10); +- StorageDead(_13); +- StorageDead(_10); ++ nop; ++ nop; StorageDead(_8); StorageDead(_7); - StorageLive(_29); @@ -213,8 +218,9 @@ StorageLive(_33); StorageLive(_34); - StorageLive(_35); +- StorageLive(_36); ++ nop; + nop; - StorageLive(_36); StorageLive(_37); _37 = &(*_1); _36 = core::str::::as_ptr(move _37) -> [return: bb8, unwind continue]; @@ -224,8 +230,9 @@ StorageDead(_37); _35 = &_36; - StorageLive(_38); +- StorageLive(_39); ++ nop; + nop; - StorageLive(_39); StorageLive(_40); _40 = &(*_29); _39 = core::slice::::as_ptr(move _40) -> [return: bb9, unwind continue]; @@ -249,11 +256,12 @@ StorageLive(_43); StorageLive(_44); - _44 = (*_41); -+ _44 = (*_35); ++ _44 = _36; StorageLive(_45); - _45 = (*_42); -+ _45 = (*_38); - _43 = Eq(move _44, move _45); +- _43 = Eq(move _44, move _45); ++ _45 = _39; ++ _43 = Eq(_36, _39); switchInt(move _43) -> [0: bb11, otherwise: bb10]; } @@ -264,8 +272,10 @@ StorageDead(_43); StorageDead(_42); StorageDead(_41); - StorageDead(_39); - StorageDead(_36); +- StorageDead(_39); +- StorageDead(_36); ++ nop; ++ nop; StorageDead(_34); StorageDead(_33); _0 = const (); diff --git a/tests/mir-opt/gvn_uninhabited.f.GVN.panic-abort.diff b/tests/mir-opt/gvn_uninhabited.f.GVN.panic-abort.diff index c5ee0d9c44d..626367766d7 100644 --- a/tests/mir-opt/gvn_uninhabited.f.GVN.panic-abort.diff +++ b/tests/mir-opt/gvn_uninhabited.f.GVN.panic-abort.diff @@ -17,7 +17,8 @@ StorageLive(_3); _5 = const f::promoted[0]; _3 = &(*_5); - _2 = ((*_3).1: E); +- _2 = ((*_3).1: E); ++ _2 = ((*_5).1: E); StorageLive(_1); - _1 = ((_2 as A).1: u32); + _1 = const 0_u32; diff --git a/tests/mir-opt/gvn_uninhabited.f.GVN.panic-unwind.diff b/tests/mir-opt/gvn_uninhabited.f.GVN.panic-unwind.diff index c5ee0d9c44d..626367766d7 100644 --- a/tests/mir-opt/gvn_uninhabited.f.GVN.panic-unwind.diff +++ b/tests/mir-opt/gvn_uninhabited.f.GVN.panic-unwind.diff @@ -17,7 +17,8 @@ StorageLive(_3); _5 = const f::promoted[0]; _3 = &(*_5); - _2 = ((*_3).1: E); +- _2 = ((*_3).1: E); ++ _2 = ((*_5).1: E); StorageLive(_1); - _1 = ((_2 as A).1: u32); + _1 = const 0_u32;