Some notes on better load folding we could do

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30155 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86RegisterInfo.cpp b/lib/Target/X86/X86RegisterInfo.cpp
index 1751e9c4d1c28ad4677165830a9ec1dba3cd6989..3a8765330dbfbca932668b92d41ec8a7cf59bc17 100644 (file)
--- a/lib/Target/X86/X86RegisterInfo.cpp
+++ b/lib/Target/X86/X86RegisterInfo.cpp
@@ -520,6 +520,7 @@ MachineInstr* X86RegisterInfo::foldMemoryOperand(MachineInstr *MI,
       { X86::TEST16rr,        X86::TEST16rm },
       { X86::TEST32rr,        X86::TEST32rm },
       { X86::TEST8rr,         X86::TEST8rm },
+      // FIXME: TEST*rr EAX,EAX ---> CMP [mem], 0
       { X86::UCOMISDrr,       X86::UCOMISDrm },
       { X86::UCOMISSrr,       X86::UCOMISSrm },
       { X86::XCHG16rr,        X86::XCHG16rm },
@@ -667,6 +668,7 @@ MachineInstr* X86RegisterInfo::foldMemoryOperand(MachineInstr *MI,
       { X86::SUBPSrr,         X86::SUBPSrm },
       { X86::SUBSDrr,         X86::SUBSDrm },
       { X86::SUBSSrr,         X86::SUBSSrm },
+      // FIXME: TEST*rr -> swapped operand of TEST*mr.
       { X86::UNPCKHPDrr,      X86::UNPCKHPDrm },
       { X86::UNPCKHPSrr,      X86::UNPCKHPSrm },
       { X86::UNPCKLPDrr,      X86::UNPCKLPDrm },