diff --git a/0001-Disable-jump-threading-of-float-equality.patch b/0001-Disable-jump-threading-of-float-equality.patch new file mode 100644 index 0000000..29093bd --- /dev/null +++ b/0001-Disable-jump-threading-of-float-equality.patch @@ -0,0 +1,212 @@ +From 49166c7dd925244f631277b4aa9ae4233f300884 Mon Sep 17 00:00:00 2001 +From: Nilstrieb <48135649+Nilstrieb@users.noreply.github.com> +Date: Sat, 27 Jul 2024 15:08:11 +0200 +Subject: [PATCH] Disable jump threading of float equality + +Jump threading stores values as `u128` (`ScalarInt`) and does its +comparisons for equality as integer comparisons. +This works great for integers. Sadly, not everything is an integer. + +Floats famously have wonky equality semantcs, with `NaN!=NaN` and +`0.0 == -0.0`. This does not match our beautiful integer bitpattern +equality and therefore causes things to go horribly wrong. + +While jump threading could be extended to support floats by remembering +that they're floats in the value state and handling them properly, +it's signficantly easier to just disable it for now. + +(cherry picked from commit eca0a7e72346ba123ace318a0f9c28c57d990aeb) +--- + .../rustc_mir_transform/src/jump_threading.rs | 7 +++ + ...ding.floats.JumpThreading.panic-abort.diff | 59 +++++++++++++++++++ + ...ing.floats.JumpThreading.panic-unwind.diff | 59 +++++++++++++++++++ + tests/mir-opt/jump_threading.rs | 12 ++++ + 4 files changed, 137 insertions(+) + create mode 100644 tests/mir-opt/jump_threading.floats.JumpThreading.panic-abort.diff + create mode 100644 tests/mir-opt/jump_threading.floats.JumpThreading.panic-unwind.diff + +diff --git a/compiler/rustc_mir_transform/src/jump_threading.rs b/compiler/rustc_mir_transform/src/jump_threading.rs +index a458297210db..e2d2864ad2a0 100644 +--- a/compiler/rustc_mir_transform/src/jump_threading.rs ++++ b/compiler/rustc_mir_transform/src/jump_threading.rs +@@ -493,6 +493,13 @@ fn process_assign( + BinOp::Ne => ScalarInt::FALSE, + _ => return None, + }; ++ if value.const_.ty().is_floating_point() { ++ // Floating point equality does not follow bit-patterns. ++ // -0.0 and NaN both have special rules for equality, ++ // and therefore we cannot use integer comparisons for them. ++ // Avoid handling them, though this could be extended in the future. ++ return None; ++ } + let value = value.const_.normalize(self.tcx, self.param_env).try_to_scalar_int()?; + let conds = conditions.map(self.arena, |c| Condition { + value, +diff --git a/tests/mir-opt/jump_threading.floats.JumpThreading.panic-abort.diff b/tests/mir-opt/jump_threading.floats.JumpThreading.panic-abort.diff +new file mode 100644 +index 000000000000..6ca37e96d297 +--- /dev/null ++++ b/tests/mir-opt/jump_threading.floats.JumpThreading.panic-abort.diff +@@ -0,0 +1,59 @@ ++- // MIR for `floats` before JumpThreading +++ // MIR for `floats` after JumpThreading ++ ++ fn floats() -> u32 { ++ let mut _0: u32; ++ let _1: f64; ++ let mut _2: bool; ++ let mut _3: bool; ++ let mut _4: f64; ++ scope 1 { ++ debug x => _1; ++ } ++ ++ bb0: { ++ StorageLive(_1); ++ StorageLive(_2); ++ _2 = const true; ++- switchInt(move _2) -> [0: bb2, otherwise: bb1]; +++ goto -> bb1; ++ } ++ ++ bb1: { ++ _1 = const -0f64; ++ goto -> bb3; ++ } ++ ++ bb2: { ++ _1 = const 1f64; ++ goto -> bb3; ++ } ++ ++ bb3: { ++ StorageDead(_2); ++ StorageLive(_3); ++ StorageLive(_4); ++ _4 = _1; ++ _3 = Eq(move _4, const 0f64); ++ switchInt(move _3) -> [0: bb5, otherwise: bb4]; ++ } ++ ++ bb4: { ++ StorageDead(_4); ++ _0 = const 0_u32; ++ goto -> bb6; ++ } ++ ++ bb5: { ++ StorageDead(_4); ++ _0 = const 1_u32; ++ goto -> bb6; ++ } ++ ++ bb6: { ++ StorageDead(_3); ++ StorageDead(_1); ++ return; ++ } ++ } ++ +diff --git a/tests/mir-opt/jump_threading.floats.JumpThreading.panic-unwind.diff b/tests/mir-opt/jump_threading.floats.JumpThreading.panic-unwind.diff +new file mode 100644 +index 000000000000..6ca37e96d297 +--- /dev/null ++++ b/tests/mir-opt/jump_threading.floats.JumpThreading.panic-unwind.diff +@@ -0,0 +1,59 @@ ++- // MIR for `floats` before JumpThreading +++ // MIR for `floats` after JumpThreading ++ ++ fn floats() -> u32 { ++ let mut _0: u32; ++ let _1: f64; ++ let mut _2: bool; ++ let mut _3: bool; ++ let mut _4: f64; ++ scope 1 { ++ debug x => _1; ++ } ++ ++ bb0: { ++ StorageLive(_1); ++ StorageLive(_2); ++ _2 = const true; ++- switchInt(move _2) -> [0: bb2, otherwise: bb1]; +++ goto -> bb1; ++ } ++ ++ bb1: { ++ _1 = const -0f64; ++ goto -> bb3; ++ } ++ ++ bb2: { ++ _1 = const 1f64; ++ goto -> bb3; ++ } ++ ++ bb3: { ++ StorageDead(_2); ++ StorageLive(_3); ++ StorageLive(_4); ++ _4 = _1; ++ _3 = Eq(move _4, const 0f64); ++ switchInt(move _3) -> [0: bb5, otherwise: bb4]; ++ } ++ ++ bb4: { ++ StorageDead(_4); ++ _0 = const 0_u32; ++ goto -> bb6; ++ } ++ ++ bb5: { ++ StorageDead(_4); ++ _0 = const 1_u32; ++ goto -> bb6; ++ } ++ ++ bb6: { ++ StorageDead(_3); ++ StorageDead(_1); ++ return; ++ } ++ } ++ +diff --git a/tests/mir-opt/jump_threading.rs b/tests/mir-opt/jump_threading.rs +index 57f4e4a2654f..3e7e8995f1a3 100644 +--- a/tests/mir-opt/jump_threading.rs ++++ b/tests/mir-opt/jump_threading.rs +@@ -514,6 +514,16 @@ fn assume(a: u8, b: bool) -> u8 { + ) + } + ++fn floats() -> u32 { ++ // CHECK-LABEL: fn floats( ++ // CHECK: switchInt( ++ ++ // Test for issue #128243, where float equality was assumed to be bitwise. ++ // When adding float support, it must be ensured that this continues working properly. ++ let x = if true { -0.0 } else { 1.0 }; ++ if x == 0.0 { 0 } else { 1 } ++} ++ + fn main() { + // CHECK-LABEL: fn main( + too_complex(Ok(0)); +@@ -528,6 +538,7 @@ fn main() { + disappearing_bb(7); + aggregate(7); + assume(7, false); ++ floats(); + } + + // EMIT_MIR jump_threading.too_complex.JumpThreading.diff +@@ -542,3 +553,4 @@ fn main() { + // EMIT_MIR jump_threading.disappearing_bb.JumpThreading.diff + // EMIT_MIR jump_threading.aggregate.JumpThreading.diff + // EMIT_MIR jump_threading.assume.JumpThreading.diff ++// EMIT_MIR jump_threading.floats.JumpThreading.diff +-- +2.46.0 + diff --git a/rust.spec b/rust.spec index f9dff9f..6bd1a47 100644 --- a/rust.spec +++ b/rust.spec @@ -1,6 +1,6 @@ Name: rust Version: 1.79.0 -Release: 1%{?dist} +Release: 2%{?dist} Summary: The Rust Programming Language License: (Apache-2.0 OR MIT) AND (Artistic-2.0 AND BSD-3-Clause AND ISC AND MIT AND MPL-2.0 AND Unicode-DFS-2016) # ^ written as: (rust itself) and (bundled libraries) @@ -160,6 +160,9 @@ Patch7: 0001-Use-an-explicit-x86-64-cpu-in-tests-that-are-sensiti.patch # Fix codegen test failure on big endian: https://github.com/rust-lang/rust/pull/126263 Patch8: 0001-Make-issue-122805.rs-big-endian-compatible.patch +# https://github.com/rust-lang/rust/pull/128271 +Patch9: 0001-Disable-jump-threading-of-float-equality.patch + ### RHEL-specific patches below ### # Simple rpm macros for rust-toolset (as opposed to full rust-packaging) @@ -641,6 +644,7 @@ rm -rf %{wasi_libc_dir}/dlmalloc/ %endif %patch -P7 -p1 %patch -P8 -p1 +%patch -P9 -p1 %if %with disabled_libssh2 %patch -P100 -p1 @@ -1142,6 +1146,9 @@ rm -rf "./build/%{rust_triple}/stage2-tools/%{rust_triple}/cit/" %changelog +* Tue Aug 13 2024 Josh Stone - 1.79.0-2 +- Disable jump threading of float equality + * Wed Jul 03 2024 Nikita Popov - 1.79.0-1 - Update to 1.79.0