diff options
| author | Bob Wilson <bob.wilson@apple.com> | 2010-08-27 23:57:52 +0000 |
|---|---|---|
| committer | Bob Wilson <bob.wilson@apple.com> | 2010-08-27 23:57:52 +0000 |
| commit | 14805e2afd5aa754e13fd5bb99365ffe972e9696 (patch) | |
| tree | 50805e7f0bb9a8888179ccae847819a41ffa0480 /lib/Target/ARM/ARMLoadStoreOptimizer.cpp | |
| parent | a0b59f6bd23afaeba923b94f46838cffd5218a12 (diff) | |
When merging Thumb2 loads/stores, do not give up when the offset is one of
the special values that for ARM would be used with IB or DA modes. Fall
through and consider materializing a new base address is it would be
profitable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112329 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/ARM/ARMLoadStoreOptimizer.cpp')
| -rw-r--r-- | lib/Target/ARM/ARMLoadStoreOptimizer.cpp | 17 |
1 files changed, 7 insertions, 10 deletions
diff --git a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp index 4fff738530..46254fdee6 100644 --- a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp +++ b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp @@ -193,20 +193,17 @@ ARMLoadStoreOpt::MergeOps(MachineBasicBlock &MBB, return false; ARM_AM::AMSubMode Mode = ARM_AM::ia; + // VFP and Thumb2 do not support IB or DA modes. bool isNotVFP = isi32Load(Opcode) || isi32Store(Opcode); - if (isNotVFP && Offset == 4) { - if (isThumb2) - // Thumb2 does not support ldmib / stmib. - return false; + bool haveIBAndDA = isNotVFP && !isThumb2; + if (Offset == 4 && haveIBAndDA) Mode = ARM_AM::ib; - } else if (isNotVFP && Offset == -4 * (int)NumRegs + 4) { - if (isThumb2) - // Thumb2 does not support ldmda / stmda. - return false; + else if (Offset == -4 * (int)NumRegs + 4 && haveIBAndDA) Mode = ARM_AM::da; - } else if (isNotVFP && Offset == -4 * (int)NumRegs) { + else if (Offset == -4 * (int)NumRegs && isNotVFP) + // VLDM/VSTM do not support DB mode without also updating the base reg. Mode = ARM_AM::db; - } else if (Offset != 0) { + else if (Offset != 0) { // If starting offset isn't zero, insert a MI to materialize a new base. // But only do so if it is cost effective, i.e. merging more than two // loads / stores. |