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authorEvan Cheng <evan.cheng@apple.com>2011-01-28 07:12:38 +0000
committerEvan Cheng <evan.cheng@apple.com>2011-01-28 07:12:38 +0000
commit1b5c0cb71dd9d529a14cedb4bd89d544bf7e61c3 (patch)
treedad2e758c2cdcb19e02be6660247761b70c4a939 /lib/CodeGen/TailDuplication.cpp
parent07317f7d333fd03ae216865a6f0e8b3bde5f030d (diff)
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Revert r124462. There are a few big regressions that I need to fix first.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124478 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/TailDuplication.cpp')
-rw-r--r--lib/CodeGen/TailDuplication.cpp11
1 files changed, 4 insertions, 7 deletions
diff --git a/lib/CodeGen/TailDuplication.cpp b/lib/CodeGen/TailDuplication.cpp
index 15aed3436c..ce4b1be854 100644
--- a/lib/CodeGen/TailDuplication.cpp
+++ b/lib/CodeGen/TailDuplication.cpp
@@ -465,12 +465,9 @@ TailDuplicatePass::TailDuplicate(MachineBasicBlock *TailBB, MachineFunction &MF,
MaxDuplicateCount = TailDuplicateSize;
if (PreRegAlloc) {
- if (TailBB->empty())
- return false;
- const TargetInstrDesc &TID = TailBB->back().getDesc();
- // Pre-regalloc tail duplication hurts compile time and doesn't help
- // much except for indirect branches and returns.
- if (!TID.isIndirectBranch() && !TID.isReturn())
+ // Pre-regalloc tail duplication hurts compile time and doesn't help
+ // much except for indirect branches.
+ if (TailBB->empty() || !TailBB->back().getDesc().isIndirectBranch())
return false;
// If the target has hardware branch prediction that can handle indirect
// branches, duplicating them can often make them predictable when there
@@ -505,7 +502,7 @@ TailDuplicatePass::TailDuplicate(MachineBasicBlock *TailBB, MachineFunction &MF,
}
// Heuristically, don't tail-duplicate calls if it would expand code size,
// as it's less likely to be worth the extra cost.
- if (InstrCount > 1 && (PreRegAlloc && HasCall))
+ if (InstrCount > 1 && HasCall)
return false;
DEBUG(dbgs() << "\n*** Tail-duplicating BB#" << TailBB->getNumber() << '\n');