[PATCH] D19410: [scan-build] fix warnings emitted on LLVM ARM code base

[Weiming Zhao via llvm-commits]

weimingz added inline comments.

================
Comment at: lib/Target/ARM/ARMFrameLowering.cpp:1610
@@ -1609,4 +1609,3 @@
   //        worth the effort and added fragility?
-  bool BigStack = (RS && (MFI->estimateStackSize(MF) +
-                              ((hasFP(MF) && AFI->hasStackFrame()) ? 4 : 0) >=
-                          estimateRSStackSizeLimit(MF, this))) ||
+  bool BigStack = ((MFI->estimateStackSize(MF) +
+                    ((hasFP(MF) && AFI->hasStackFrame()) ? 4 : 0) >=
----------------
compnerd wrote:
> rengolin wrote:
> > Better ask @weimingz about this one.
> Ugh, this is *subtle*.  If we are going to simplify this, please add a couple of asserts.
> 
>     assert(requiresRegisterScavenging() && "ARM requires register scavenging");
>     assert(RS && "Target requiring register scavenging not provided register scavenger");
Agree. We need to simplify the BigStack test. It's hard to read.

 It would be better if we refactor it to:

unsigned EstimatedStackSize  = MFI->estimateStackSize(MF) + ...

bool BgsTack = EstimatedStackSize >= estimatedRSStackSizeLImit() || ... || ...
 


http://reviews.llvm.org/D19410