[ConstraintElim] Enable pass by default.

The pass should help to close a functional gap when it comes to
reasoning about related conditions in a relatively general way.

It addresses multiple existing issues (linked below) and the need for a
more powerful reasoning system was also discussed recently in
https://discourse.llvm.org/t/rfc-alternative-approach-of-dealing-with-implications-from-comparisons-through-pos-analysis/65601/7

On AArch64, the new pass performs ~2000 simplifications on
MultiSource,SPEC2006,SPEC2017 with -O3.

Compile-time impact:

NewPM-O3: +0.20%
NewPM-ReleaseThinLTO: +0.32%
NewPM-ReleaseLTO-g: +0.28%

https://llvm-compile-time-tracker.com/compare.php?from=f01a3a893c147c1594b9a3fbd817456b209dabbf&to=577688758ef64fb044215ec3e497ea901bb2db28&stat=instructions:u

Fixes #49344.
Fixes #47888.
Fixes #48253.
Fixes #49229.
Fixes #58074.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D135915

diff --git a/llvm/lib/Passes/PassBuilderPipelines.cpp b/llvm/lib/Passes/PassBuilderPipelines.cpp
index 83d69ec..1e49550 100644 (file)
--- a/llvm/lib/Passes/PassBuilderPipelines.cpp
+++ b/llvm/lib/Passes/PassBuilderPipelines.cpp
@@ -263,7 +263,7 @@ static cl::opt<bool>
                  cl::desc("Enable lowering of the matrix intrinsics"));
 
 static cl::opt<bool> EnableConstraintElimination(
-    "enable-constraint-elimination", cl::init(false), cl::Hidden,
+    "enable-constraint-elimination", cl::init(true), cl::Hidden,
     cl::desc(
         "Enable pass to eliminate conditions based on linear constraints"));
 

diff --git a/llvm/test/Other/new-pm-defaults.ll b/llvm/test/Other/new-pm-defaults.ll
index fbcd1ed..71c27ee 100644 (file)
--- a/llvm/test/Other/new-pm-defaults.ll
+++ b/llvm/test/Other/new-pm-defaults.ll
@@ -154,6 +154,7 @@
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O3-NEXT: AggressiveInstCombinePass
+; CHECK-O23SZ-NEXT: Running pass: ConstraintEliminationPass
 ; CHECK-O1-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O2-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O3-NEXT: Running pass: LibCallsShrinkWrapPass

diff --git a/llvm/test/Other/new-pm-lto-defaults.ll b/llvm/test/Other/new-pm-lto-defaults.ll
index 2ae507d..b533ad3 100644 (file)
--- a/llvm/test/Other/new-pm-lto-defaults.ll
+++ b/llvm/test/Other/new-pm-lto-defaults.ll
@@ -89,6 +89,7 @@
 ; CHECK-O23SZ-NEXT: Running pass: DeadArgumentEliminationPass
 ; CHECK-O23SZ-NEXT: Running pass: InstCombinePass
 ; CHECK-EP-Peephole-NEXT: Running pass: NoOpFunctionPass
+; CHECK-O23SZ-NEXT: Running pass: ConstraintEliminationPass
 ; CHECK-O23SZ-NEXT: Running pass: JumpThreadingPass
 ; CHECK-O23SZ-NEXT: Running analysis: LazyValueAnalysis
 ; CHECK-O23SZ-NEXT: Running pass: SROAPass on foo

diff --git a/llvm/test/Other/new-pm-thinlto-defaults.ll b/llvm/test/Other/new-pm-thinlto-defaults.ll
index 23ace38..5ca59b5 100644 (file)
--- a/llvm/test/Other/new-pm-thinlto-defaults.ll
+++ b/llvm/test/Other/new-pm-thinlto-defaults.ll
@@ -130,6 +130,7 @@
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O3-NEXT: Running pass: AggressiveInstCombinePass
+; CHECK-O23SZ-NEXT: Running pass: ConstraintEliminationPass
 ; CHECK-O1-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O2-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O3-NEXT: Running pass: LibCallsShrinkWrapPass

diff --git a/llvm/test/Other/new-pm-thinlto-postlink-pgo-defaults.ll b/llvm/test/Other/new-pm-thinlto-postlink-pgo-defaults.ll
index b1e716f..cd1fe43 100644 (file)
--- a/llvm/test/Other/new-pm-thinlto-postlink-pgo-defaults.ll
+++ b/llvm/test/Other/new-pm-thinlto-postlink-pgo-defaults.ll
@@ -92,6 +92,7 @@
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O3-NEXT: Running pass: AggressiveInstCombinePass
+; CHECK-O23SZ-NEXT: Running pass: ConstraintEliminationPass
 ; CHECK-O1-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O2-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O3-NEXT: Running pass: LibCallsShrinkWrapPass

diff --git a/llvm/test/Other/new-pm-thinlto-postlink-samplepgo-defaults.ll b/llvm/test/Other/new-pm-thinlto-postlink-samplepgo-defaults.ll
index 4e0432e..3ec9a30 100644 (file)
--- a/llvm/test/Other/new-pm-thinlto-postlink-samplepgo-defaults.ll
+++ b/llvm/test/Other/new-pm-thinlto-postlink-samplepgo-defaults.ll
@@ -101,6 +101,7 @@
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O3-NEXT: Running pass: AggressiveInstCombinePass
+; CHECK-O23SZ-NEXT: Running pass: ConstraintEliminationPass
 ; CHECK-O1-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O2-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O3-NEXT: Running pass: LibCallsShrinkWrapPass

diff --git a/llvm/test/Other/new-pm-thinlto-prelink-pgo-defaults.ll b/llvm/test/Other/new-pm-thinlto-prelink-pgo-defaults.ll
index a1ac98f..5738e0c 100644 (file)
--- a/llvm/test/Other/new-pm-thinlto-prelink-pgo-defaults.ll
+++ b/llvm/test/Other/new-pm-thinlto-prelink-pgo-defaults.ll
@@ -128,6 +128,7 @@
 ; CHECK-O-DAG: Running analysis: BranchProbabilityAnalysis on foo
 ; CHECK-O-DAG: Running analysis: PostDominatorTreeAnalysis on foo
 ; CHECK-O3-NEXT: Running pass: AggressiveInstCombinePass
+; CHECK-O23SZ-NEXT: Running pass: ConstraintEliminationPass
 ; CHECK-O1-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O2-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O3-NEXT: Running pass: LibCallsShrinkWrapPass

diff --git a/llvm/test/Other/new-pm-thinlto-prelink-samplepgo-defaults.ll b/llvm/test/Other/new-pm-thinlto-prelink-samplepgo-defaults.ll
index 386f08a..b2109eb 100644 (file)
--- a/llvm/test/Other/new-pm-thinlto-prelink-samplepgo-defaults.ll
+++ b/llvm/test/Other/new-pm-thinlto-prelink-samplepgo-defaults.ll
@@ -96,6 +96,7 @@
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O3-NEXT: Running pass: AggressiveInstCombinePass
+; CHECK-O23SZ-NEXT: Running pass: ConstraintEliminationPass
 ; CHECK-O1-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O2-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O3-NEXT: Running pass: LibCallsShrinkWrapPass