[ConstHoisting] Turn on consthoist-with-block-frequency by default.

Using profile information to guide consthoisting is generally helpful for
performance, so the patch turns it on by default. No compile time or perf
regression were found using spec2000 and spec2006 on x86.  Some significant
improvement (>20%) was seen on internal benchmarks.

Differential Revision: https://reviews.llvm.org/D35063

llvm-svn: 307338

diff --git a/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp b/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp
index 5f4a785..14638e8 100644 (file)
--- a/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp
+++ b/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp
@@ -55,7 +55,7 @@ STATISTIC(NumConstantsHoisted, "Number of constants hoisted");
 STATISTIC(NumConstantsRebased, "Number of constants rebased");
 
 static cl::opt<bool> ConstHoistWithBlockFrequency(
-    "consthoist-with-block-frequency", cl::init(false), cl::Hidden,
+    "consthoist-with-block-frequency", cl::init(true), cl::Hidden,
     cl::desc("Enable the use of the block frequency analysis to reduce the "
              "chance to execute const materialization more frequently than "
              "without hoisting."));

diff --git a/llvm/test/Transforms/ConstantHoisting/X86/ehpad.ll b/llvm/test/Transforms/ConstantHoisting/X86/ehpad.ll
index 4f87572..5e345c4 100644 (file)
--- a/llvm/test/Transforms/ConstantHoisting/X86/ehpad.ll
+++ b/llvm/test/Transforms/ConstantHoisting/X86/ehpad.ll
@@ -1,9 +1,6 @@
-; RUN: opt -S -consthoist < %s | FileCheck %s
+; RUN: opt -S -consthoist -consthoist-with-block-frequency=false < %s | FileCheck %s
 ; RUN: opt -S -consthoist -consthoist-with-block-frequency=true < %s | FileCheck --check-prefix=BFIHOIST %s
 
-; FIXME: The catchpad doesn't even use the constant, so a better fix would be to
-; insert the bitcast in the catchpad block.
-
 target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-pc-windows-msvc"