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author | Evan Cheng <evan.cheng@apple.com> | 2011-01-07 23:50:32 +0000 |
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committer | Evan Cheng <evan.cheng@apple.com> | 2011-01-07 23:50:32 +0000 |
commit | c36b7069b42bece963b7e6adf020353ce990ef76 (patch) | |
tree | fdbe6e1cede36ae3485403b9165bfdc039056eeb /lib/CodeGen/VirtRegRewriter.cpp | |
parent | 067a16c974fef473fd3bca1d58db0d50c59882ce (diff) | |
download | llvm-c36b7069b42bece963b7e6adf020353ce990ef76.tar.gz llvm-c36b7069b42bece963b7e6adf020353ce990ef76.tar.bz2 llvm-c36b7069b42bece963b7e6adf020353ce990ef76.tar.xz |
Do not model all INLINEASM instructions as having unmodelled side effects.
Instead encode llvm IR level property "HasSideEffects" in an operand (shared
with IsAlignStack). Added MachineInstrs::hasUnmodeledSideEffects() to check
the operand when the instruction is an INLINEASM.
This allows memory instructions to be moved around INLINEASM instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123044 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/VirtRegRewriter.cpp')
-rw-r--r-- | lib/CodeGen/VirtRegRewriter.cpp | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/lib/CodeGen/VirtRegRewriter.cpp b/lib/CodeGen/VirtRegRewriter.cpp index d04b9285ba..87781067ef 100644 --- a/lib/CodeGen/VirtRegRewriter.cpp +++ b/lib/CodeGen/VirtRegRewriter.cpp @@ -1620,9 +1620,16 @@ static bool isSafeToDelete(MachineInstr &MI) { const TargetInstrDesc &TID = MI.getDesc(); if (TID.mayLoad() || TID.mayStore() || TID.isCall() || TID.isTerminator() || TID.isCall() || TID.isBarrier() || TID.isReturn() || - TID.hasUnmodeledSideEffects() || - MI.isLabel() || MI.isDebugValue()) + MI.isLabel() || MI.isDebugValue() || + MI.hasUnmodeledSideEffects()) return false; + + // Technically speaking inline asm without side effects and no defs can still + // be deleted. But there is so much bad inline asm code out there, we should + // let them be. + if (MI.isInlineAsm()) + return false; + for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) { MachineOperand &MO = MI.getOperand(i); if (!MO.isReg() || !MO.getReg()) |