- Make sure we keep -DNDEBUG. At some point %{optflags} must have

lost it, perhaps because CMake usually adds it on top. So when overriding CMAKE_{C,CXX}_FLAGS_RELWITHDEBINFO, we make sure to take over the other flags. We drop LLVM_ENABLE_ASSERTIONS=OFF, because that's the default anyway and hasn't helped here. - Add llvm-scev-fix-isImpliedViaMerge.patch: fixes a miscompilation caused by mixing up values of the current and previous iteration. (See gh#llvm/llvm-project#56242.) OBS-URL: https://build.opensuse.org/package/show/devel:tools:compiler/llvm14?expand=0&rev=38
2022-09-03 16:28:17 +00:00 · 2022-09-03 16:28:17 +00:00 · 50afd4a305
commit 50afd4a305
parent 111d72ecd8
3 changed files with 172 additions and 4 deletions
--- a/llvm-scev-fix-isImpliedViaMerge.patch
+++ b/llvm-scev-fix-isImpliedViaMerge.patch
@ -0,0 +1,155 @@
+From cfb4c1a735e9648ead5bf60a1fab4f09b5ee6453 Mon Sep 17 00:00:00 2001
+From: Nikita Popov <npopov@redhat.com>
+Date: Mon, 27 Jun 2022 14:54:03 +0200
+Subject: [PATCH] [IndVars] Add test for PR56242 (NFC)
+
+---
+ .../test/Transforms/IndVarSimplify/pr56242.ll | 49 +++++++++++++++++++
+ 1 file changed, 49 insertions(+)
+ create mode 100644 llvm/test/Transforms/IndVarSimplify/pr56242.ll
+
+diff --git a/llvm/test/Transforms/IndVarSimplify/pr56242.ll b/llvm/test/Transforms/IndVarSimplify/pr56242.ll
+new file mode 100644
+index 0000000000000..82e1d2252e760
+--- /dev/null
+++ b/llvm/test/Transforms/IndVarSimplify/pr56242.ll
+@@ -0,0 +1,49 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -indvars < %s | FileCheck %s
+
+declare void @use(i1)
+
+define void @test(ptr %arr) {
+; CHECK-LABEL: @test(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br label [[LOOP_HEADER:%.*]]
+; CHECK:       loop.header:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[IV_INC:%.*]], [[LOOP_LATCH:%.*]] ], [ 0, [[ENTRY:%.*]] ]
+; CHECK-NEXT:    [[PTR:%.*]] = getelementptr inbounds i32, ptr [[ARR:%.*]], i64 [[IV]]
+; CHECK-NEXT:    [[V:%.*]] = load i32, ptr [[PTR]], align 4
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp sgt i32 [[V]], 0
+; CHECK-NEXT:    br i1 [[CMP1]], label [[IF:%.*]], label [[LOOP_LATCH]]
+; CHECK:       if:
+; CHECK-NEXT:    call void @use(i1 false)
+; CHECK-NEXT:    br label [[LOOP_LATCH]]
+; CHECK:       loop.latch:
+; CHECK-NEXT:    [[IV_INC]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[IV_INC]], 16
+; CHECK-NEXT:    br i1 [[CMP]], label [[LOOP_HEADER]], label [[EXIT:%.*]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
+entry:
+  br label %loop.header
+
+loop.header:
+  %iv = phi i64 [ %iv.inc, %loop.latch ], [ 0, %entry ]
+  %prev = phi i32 [ %v, %loop.latch ], [ 0, %entry ]
+  %ptr = getelementptr inbounds i32, ptr %arr, i64 %iv
+  %v = load i32, ptr %ptr
+  %cmp1 = icmp sgt i32 %v, 0
+  br i1 %cmp1, label %if, label %loop.latch
+
+if:
+  %cmp2 = icmp slt i32 %prev, 0
+  call void @use(i1 %cmp2)
+  br label %loop.latch
+
+loop.latch:
+  %iv.inc = add nuw nsw i64 %iv, 1
+  %cmp = icmp ult i64 %iv.inc, 16
+  br i1 %cmp, label %loop.header, label %exit
+
+exit:
+  ret void
+}
+
+From e4d1d0cc2c9ca38f98bc9b70c3e3db3a18f1e06e Mon Sep 17 00:00:00 2001
+From: Nikita Popov <npopov@redhat.com>
+Date: Mon, 27 Jun 2022 15:09:24 +0200
+Subject: [PATCH] [SCEV] Fix isImpliedViaMerge() with values from previous
+ iteration (PR56242)
+
+When trying to prove an implied condition on a phi by proving it
+for all incoming values, we need to be careful about values coming
+from a backedge, as these may refer to a previous loop iteration.
+A variant of this issue was fixed in D101829, but the dominance
+condition used there isn't quite right: It checks that the value
+dominates the incoming block, which doesn't exclude backedges
+(values defined in a loop will usually dominate the loop latch,
+which is the incoming block of the backedge).
+
+Instead, we should be checking for domination of the phi block.
+Any values defined inside the loop will not dominate the loop
+header phi.
+
+Fixes https://github.com/llvm/llvm-project/issues/56242.
+
+Differential Revision: https://reviews.llvm.org/D128640
+---
+ llvm/lib/Analysis/ScalarEvolution.cpp          |  2 +-
+ llvm/test/Transforms/IRCE/decrementing-loop.ll | 11 +++++------
+ llvm/test/Transforms/IndVarSimplify/pr56242.ll |  6 ++++--
+ 3 files changed, 10 insertions(+), 9 deletions(-)
+
+diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
+index aa349f9435ce9..968665c4d3876 100644
+--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
+@@ -11812,7 +11812,7 @@ bool ScalarEvolution::isImpliedViaMerge(ICmpInst::Predicate Pred,
+       const SCEV *L = getSCEV(LPhi->getIncomingValueForBlock(IncBB));
+       // Make sure L does not refer to a value from a potentially previous
+       // iteration of a loop.
+-      if (!properlyDominates(L, IncBB))
+      if (!properlyDominates(L, LBB))
+         return false;
+       if (!ProvedEasily(L, RHS))
+         return false;
+diff --git a/llvm/test/Transforms/IRCE/decrementing-loop.ll b/llvm/test/Transforms/IRCE/decrementing-loop.ll
+index 5ae4412b34bd7..462607162bcbe 100644
+--- a/llvm/test/Transforms/IRCE/decrementing-loop.ll
+++ b/llvm/test/Transforms/IRCE/decrementing-loop.ll
+@@ -210,17 +210,16 @@ exit:
+   ret void
+ }
+ 
+-; TODO: we need to be more careful when trying to look through phi nodes in
+-; cycles, because the condition to prove may reference the previous value of
+-; the phi. So we currently fail to optimize this case.
+ ; Check that we can figure out that IV is non-negative via implication through
+ ; two Phi nodes, one being AddRec.
+ define void @test_05(i32* %a, i32* %a_len_ptr, i1 %cond) {
+ 
+ ; CHECK-LABEL: test_05
+-; CHECK: entry:
+-; CHECK:   br label %merge
+-; CHECK-NOT: mainloop
+; CHECK:       mainloop:
+; CHECK-NEXT:    br label %loop
+; CHECK:       loop:
+; CHECK:         br i1 true, label %in.bounds, label %out.of.bounds
+; CHECK:       loop.preloop:
+ 
+  entry:
+   %len.a = load i32, i32* %a_len_ptr, !range !0
+diff --git a/llvm/test/Transforms/IndVarSimplify/pr56242.ll b/llvm/test/Transforms/IndVarSimplify/pr56242.ll
+index 82e1d2252e760..6afed4177e1f7 100644
+--- a/llvm/test/Transforms/IndVarSimplify/pr56242.ll
+++ b/llvm/test/Transforms/IndVarSimplify/pr56242.ll
+@@ -9,12 +9,14 @@ define void @test(ptr %arr) {
+ ; CHECK-NEXT:    br label [[LOOP_HEADER:%.*]]
+ ; CHECK:       loop.header:
+ ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[IV_INC:%.*]], [[LOOP_LATCH:%.*]] ], [ 0, [[ENTRY:%.*]] ]
+; CHECK-NEXT:    [[PREV:%.*]] = phi i32 [ [[V:%.*]], [[LOOP_LATCH]] ], [ 0, [[ENTRY]] ]
+ ; CHECK-NEXT:    [[PTR:%.*]] = getelementptr inbounds i32, ptr [[ARR:%.*]], i64 [[IV]]
+-; CHECK-NEXT:    [[V:%.*]] = load i32, ptr [[PTR]], align 4
+; CHECK-NEXT:    [[V]] = load i32, ptr [[PTR]], align 4
+ ; CHECK-NEXT:    [[CMP1:%.*]] = icmp sgt i32 [[V]], 0
+ ; CHECK-NEXT:    br i1 [[CMP1]], label [[IF:%.*]], label [[LOOP_LATCH]]
+ ; CHECK:       if:
+-; CHECK-NEXT:    call void @use(i1 false)
+; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i32 [[PREV]], 0
+; CHECK-NEXT:    call void @use(i1 [[CMP2]])
+ ; CHECK-NEXT:    br label [[LOOP_LATCH]]
+ ; CHECK:       loop.latch:
+ ; CHECK-NEXT:    [[IV_INC]] = add nuw nsw i64 [[IV]], 1
--- a/llvm14.changes
+++ b/llvm14.changes
@ -1,3 +1,15 @@
+-------------------------------------------------------------------
+Sat Sep  3 15:15:10 UTC 2022 - Aaron Puchert <aaronpuchert@alice-dsl.net>
+
+- Make sure we keep -DNDEBUG. At some point %{optflags} must have
+  lost it, perhaps because CMake usually adds it on top. So when
+  overriding CMAKE_{C,CXX}_FLAGS_RELWITHDEBINFO, we make sure to
+  take over the other flags. We drop LLVM_ENABLE_ASSERTIONS=OFF,
+  because that's the default anyway and hasn't helped here.
+- Add llvm-scev-fix-isImpliedViaMerge.patch: fixes a miscompilation
+  caused by mixing up values of the current and previous iteration.
+  (See gh#llvm/llvm-project#56242.)
+
 -------------------------------------------------------------------
 Fri Aug 26 21:18:56 UTC 2022 - Aaron Puchert <aaronpuchert@alice-dsl.net>

--- a/llvm14.spec
+++ b/llvm14.spec
@ -368,6 +368,8 @@ Patch24:        opt-viewer-Find-style-css-in-usr-share.patch
 Patch25:        check-no-llvm-exegesis.patch
 # PATCH-FIX-OPENSUSE lld-default-sha1.patch
 Patch26:        lld-default-sha1.patch
+# Fix for https://github.com/llvm/llvm-project/issues/56242.
+Patch27:        llvm-scev-fix-isImpliedViaMerge.patch
 # Fix lookup of targets in installed CMake files. (boo#1180748, https://reviews.llvm.org/D96670)
 Patch33:        CMake-Look-up-target-subcomponents-in-LLVM_AVAILABLE_LIBS.patch
 # Make link dependencies of clang-repl private (https://reviews.llvm.org/D122546).
@ -801,6 +803,7 @@ This package contains the development files for Polly.
 %patch22 -p1
 %patch24 -p1
 %patch25 -p2
+%patch27 -p2
 %patch33 -p2

 pushd clang-%{_version}.src
@ -938,7 +941,6 @@ avail_mem=$(awk '/MemAvailable/ { print $2 }' /proc/meminfo)
    -DLLVM_TOOL_CLANG_TOOLS_EXTRA_BUILD:BOOL=OFF \
    -DLLVM_INCLUDE_BENCHMARKS:BOOL=OFF \
    -DLLVM_INCLUDE_TESTS:BOOL=OFF \
-    -DLLVM_ENABLE_ASSERTIONS=OFF \
    -DLLVM_TARGETS_TO_BUILD=Native \
    -DCLANG_ENABLE_ARCMT:BOOL=OFF \
    -DCLANG_ENABLE_STATIC_ANALYZER:BOOL=OFF \
@ -1010,14 +1012,13 @@ export LD_LIBRARY_PATH=%{sourcedir}/build/%{_lib}
 %endif
 %endif
 %ifarch %arm ppc s390 %{ix86}
-    -DCMAKE_C_FLAGS_RELWITHDEBINFO="-g1" \
-    -DCMAKE_CXX_FLAGS_RELWITHDEBINFO="-g1" \
+    -DCMAKE_C_FLAGS_RELWITHDEBINFO="-O2 -g1 -DNDEBUG" \
+    -DCMAKE_CXX_FLAGS_RELWITHDEBINFO="-O2 -g1 -DNDEBUG" \
 %endif
    -DENABLE_LINKER_BUILD_ID=ON \
    -DLLVM_TABLEGEN="%{sourcedir}/stage1/bin/llvm-tblgen" \
    -DCLANG_TABLEGEN="%{sourcedir}/stage1/bin/clang-tblgen" \
    -DLLVM_ENABLE_RTTI:BOOL=ON \
-    -DLLVM_ENABLE_ASSERTIONS=OFF \
    -DLLVM_ENABLE_PIC=ON \
    -DLLVM_BINUTILS_INCDIR=%{_includedir} \
    -DLLVM_TARGETS_TO_BUILD=%{llvm_targets} \