Change MRegisterDesc::AliasSet, TargetInstrDescriptor::ImplicitDefs

and TargetInstrDescriptor::ImplicitUses to always point to a null
terminated array and never be null. So there is no need to check for
pointer validity when iterating over those sets. Code that looked
like:

if (const unsigned* AS = TID.ImplicitDefs) {
  for (int i = 0; AS[i]; ++i) {
    // use AS[i]
  }
}

was changed to:

for (const unsigned* AS = TID.ImplicitDefs; *AS; ++AS) {
  // use *AS
}


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8960 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 6 deletions

diff --git a/lib/CodeGen/RegAllocSimple.cpp b/lib/CodeGen/RegAllocSimple.cpp
index 57d678b..dbf731e 100644
--- a/lib/CodeGen/RegAllocSimple.cpp
+++ b/lib/CodeGen/RegAllocSimple.cpp
@@ -153,13 +153,13 @@ void RegAllocSimple::AllocateBasicBlock(MachineBasicBlock &MBB) {
     // are used by the instruction (including implicit uses)
     unsigned Opcode = MI->getOpcode();
     const TargetInstrDescriptor &Desc = TM->getInstrInfo().get(Opcode);
-    if (const unsigned *Regs = Desc.ImplicitUses)
-      while (*Regs)
-	RegsUsed[*Regs++] = true;
+    const unsigned *Regs = Desc.ImplicitUses;
+    while (*Regs)
+      RegsUsed[*Regs++] = true;
     
-    if (const unsigned *Regs = Desc.ImplicitDefs)
-      while (*Regs)
-	RegsUsed[*Regs++] = true;
+    Regs = Desc.ImplicitDefs;
+    while (*Regs)
+      RegsUsed[*Regs++] = true;
     
     // Loop over uses, move from memory into registers
     for (int i = MI->getNumOperands() - 1; i >= 0; --i) {