llvm-project

Commit Graph

Author	SHA1	Message	Date
David Green	4511f3fa86	[SCEV] Ensure that isHighCostExpansion takes into account what is being divided A SCEV is not low-cost just because you can divide it by a power of 2. We need to also check what we are dividing to make sure it too is not a high-code expansion. This helps to not expand the exit value of certain loops, helping not to bloat the code. The change in no-iv-rewrite.ll is reverting back to what it was testing before rL194116, and looks a lot like the other tests in replace-loop-exit-folds.ll. Differential Revision: https://reviews.llvm.org/D58435 llvm-svn: 355393	2019-03-05 12:12:18 +00:00
David Green	3bcb0aa7f9	[SCEV] Add some extra tests for IndVarSimplifys loop exit values. NFC. Add some tests for various loops of the form: while(S >= 32) { S -= 32; something(); }; return S; llvm-svn: 355389	2019-03-05 11:18:55 +00:00

Author

SHA1

Message

Date

David Green

4511f3fa86

[SCEV] Ensure that isHighCostExpansion takes into account what is being divided

A SCEV is not low-cost just because you can divide it by a power of 2. We need to also
check what we are dividing to make sure it too is not a high-code expansion. This helps
to not expand the exit value of certain loops, helping not to bloat the code.

The change in no-iv-rewrite.ll is reverting back to what it was testing before rL194116,
and looks a lot like the other tests in replace-loop-exit-folds.ll.

Differential Revision: https://reviews.llvm.org/D58435

llvm-svn: 355393

2019-03-05 12:12:18 +00:00

David Green

3bcb0aa7f9

[SCEV] Add some extra tests for IndVarSimplifys loop exit values. NFC.

Add some tests for various loops of the form:
  while(S >= 32) {
    S -= 32;
    something();
  };
  return S;

llvm-svn: 355389

2019-03-05 11:18:55 +00:00

2 Commits