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| author | Sanjay Patel <spatel@rotateright.com> | 2015-07-30 21:41:50 +0000 |
|---|---|---|
| committer | Sanjay Patel <spatel@rotateright.com> | 2015-07-30 21:41:50 +0000 |
| commit | 1166f2ff9f30a84fea630888b297bf58c3dba7e9 (patch) | |
| tree | 80e04d68cbf5db5d6a91f2c552dc5f0fff249ca8 /llvm/lib/Target/X86/X86ISelLowering.cpp | |
| parent | 0deb694d943f914657437229f077b64aacf4fec7 (diff) | |
| download | bcm5719-llvm-1166f2ff9f30a84fea630888b297bf58c3dba7e9.tar.gz bcm5719-llvm-1166f2ff9f30a84fea630888b297bf58c3dba7e9.zip | |
fix memcpy/memset/memmove lowering when optimizing for size
Fixing MinSize attribute handling was discussed in D11363.
This is a prerequisite patch to doing that.
The handling of OptSize when lowering mem* functions was broken
on Darwin because it wants to ignore -Os for these cases, but the
existing logic also made it ignore -Oz (MinSize).
The Linux change demonstrates a widespread problem. The backend
doesn't usually recognize the MinSize attribute by itself; it
assumes that if the MinSize attribute exists, then the OptSize
attribute must also exist.
Fixing this more generally will be a follow-on patch or two.
Differential Revision: http://reviews.llvm.org/D11568
llvm-svn: 243693
Diffstat (limited to 'llvm/lib/Target/X86/X86ISelLowering.cpp')
| -rw-r--r-- | llvm/lib/Target/X86/X86ISelLowering.cpp | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp index 906f0464d84..1788edcaf78 100644 --- a/llvm/lib/Target/X86/X86ISelLowering.cpp +++ b/llvm/lib/Target/X86/X86ISelLowering.cpp @@ -1723,14 +1723,12 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM, computeRegisterProperties(Subtarget->getRegisterInfo()); - // On Darwin, -Os means optimize for size without hurting performance, - // do not reduce the limit. MaxStoresPerMemset = 16; // For @llvm.memset -> sequence of stores - MaxStoresPerMemsetOptSize = Subtarget->isTargetDarwin() ? 16 : 8; + MaxStoresPerMemsetOptSize = 8; MaxStoresPerMemcpy = 8; // For @llvm.memcpy -> sequence of stores - MaxStoresPerMemcpyOptSize = Subtarget->isTargetDarwin() ? 8 : 4; + MaxStoresPerMemcpyOptSize = 4; MaxStoresPerMemmove = 8; // For @llvm.memmove -> sequence of stores - MaxStoresPerMemmoveOptSize = Subtarget->isTargetDarwin() ? 8 : 4; + MaxStoresPerMemmoveOptSize = 4; setPrefLoopAlignment(4); // 2^4 bytes. // Predictable cmov don't hurt on atom because it's in-order. |
