[PowerPC] Refactor getMinCallFrameSize / getMinCallArgumentsSize

As of r211495, the only remaining users of getMinCallFrameSize are in
core ABI code (LowerFormalParameter / LowerCall).  This is actually a
good thing, since the details of the parameter save area are ABI specific.

With the new ELFv2 ABI in particular, the rules defining the size of the
save area will become significantly more complex, so it wouldn't make
sense to implement those outside ABI code that has all required
information.

In preparation, this patch eliminates the getMinCallFrameSize (and
associated getMinCallArgumentsSize) routines, and inlines them into all
callers.  Note that since nearly all call arguments are constant, this
allows simplifying the inlined copies to a single line everywhere.

No change in generate code expected.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211497 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/PowerPC/PPCFastISel.cpp

@@ -1199,7 +1199,8 @@ bool PPCFastISel::processCallArgs(SmallVectorImpl<Value*> &Args,
   CCState CCInfo(CC, IsVarArg, *FuncInfo.MF, TM, ArgLocs, *Context);
 
   // Reserve space for the linkage area on the stack.
-  CCInfo.AllocateStack(PPCFrameLowering::getLinkageSize(true, false), 8);
+  unsigned LinkageSize = PPCFrameLowering::getLinkageSize(true, false);
+  CCInfo.AllocateStack(LinkageSize, 8);
 
   CCInfo.AnalyzeCallOperands(ArgVTs, ArgFlags, CC_PPC64_ELF_FIS);
 
@@ -1227,8 +1228,7 @@ bool PPCFastISel::processCallArgs(SmallVectorImpl<Value*> &Args,
   // Because we cannot tell if this is needed on the caller side, we have to
   // conservatively assume that it is needed.  As such, make sure we have at
   // least enough stack space for the caller to store the 8 GPRs.
-  NumBytes = std::max(NumBytes,
-                      PPCFrameLowering::getMinCallFrameSize(true, false));
+  NumBytes = std::max(NumBytes, LinkageSize + 64);
 
   // Issue CALLSEQ_START.
   BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,