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author | Anton Korobeynikov <asl@math.spbu.ru> | 2008-04-23 18:23:30 +0000 |
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committer | Anton Korobeynikov <asl@math.spbu.ru> | 2008-04-23 18:23:30 +0000 |
commit | d52bdaff0c73c105167b70941af245f46b70753f (patch) | |
tree | e5f4945acfb09c5be4e43182d0a0a4f3ab236ec6 /lib/Target | |
parent | 856914fe0084278d11edec79c8b707a6276b8857 (diff) | |
download | llvm-d52bdaff0c73c105167b70941af245f46b70753f.tar.gz llvm-d52bdaff0c73c105167b70941af245f46b70753f.tar.bz2 llvm-d52bdaff0c73c105167b70941af245f46b70753f.tar.xz |
Be over-conservative: scan for all used virtual registers and calculate maximal stack alignment in assumption, that there will be spill of vector register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50167 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target')
-rw-r--r-- | lib/Target/X86/X86RegisterInfo.cpp | 11 | ||||
-rw-r--r-- | lib/Target/X86/X86TargetMachine.cpp | 2 |
2 files changed, 11 insertions, 2 deletions
diff --git a/lib/Target/X86/X86RegisterInfo.cpp b/lib/Target/X86/X86RegisterInfo.cpp index 2b14f6eb9b..0d528f7258 100644 --- a/lib/Target/X86/X86RegisterInfo.cpp +++ b/lib/Target/X86/X86RegisterInfo.cpp @@ -1121,11 +1121,18 @@ namespace { virtual bool runOnMachineFunction(MachineFunction &MF) { MachineFrameInfo *FFI = MF.getFrameInfo(); + MachineRegisterInfo &RI = MF.getRegInfo(); - // Calculate and set max stack object alignment early, so we can decide - // whether we will need stack realignment (and thus FP). + // Calculate max stack alignment of all already allocated stack objects. unsigned MaxAlign = calculateMaxStackAlignment(FFI); + // Be over-conservative: scan over all vreg defs and find, whether vector + // registers are used. If yes - there is probability, that vector register + // will be spilled and thus stack needs to be aligned properly. + for (unsigned RegNum = TargetRegisterInfo::FirstVirtualRegister; + RegNum < RI.getLastVirtReg(); ++RegNum) + MaxAlign = std::max(MaxAlign, RI.getRegClass(RegNum)->getAlignment()); + FFI->setMaxAlignment(MaxAlign); return false; diff --git a/lib/Target/X86/X86TargetMachine.cpp b/lib/Target/X86/X86TargetMachine.cpp index f75a77c6b0..218f356b92 100644 --- a/lib/Target/X86/X86TargetMachine.cpp +++ b/lib/Target/X86/X86TargetMachine.cpp @@ -162,6 +162,8 @@ bool X86TargetMachine::addInstSelector(PassManagerBase &PM, bool Fast) { } bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM, bool Fast) { + // Calculate and set max stack object alignment early, so we can decide + // whether we will need stack realignment (and thus FP). PM.add(createX86MaxStackAlignmentCalculatorPass()); return false; // -print-machineinstr shouldn't print after this. } |