diff options
| author | Reid Kleckner <rnk@google.com> | 2018-08-14 17:35:35 +0000 |
|---|---|---|
| committer | Reid Kleckner <rnk@google.com> | 2018-08-14 17:35:35 +0000 |
| commit | a7a21e64cbecca29e89747bd98b85792a7539d25 (patch) | |
| tree | 2c1b8cd8f3f65369c58b4e3a19e7699c4fac1371 /llvm/lib/CodeGen/MacroFusion.cpp | |
| parent | 599b2d122fd17b8468454dfe052ceca4fcedba63 (diff) | |
| download | bcm5719-llvm-a7a21e64cbecca29e89747bd98b85792a7539d25.tar.gz bcm5719-llvm-a7a21e64cbecca29e89747bd98b85792a7539d25.zip | |
Merging r339636:
------------------------------------------------------------------------
r339636 | rnk | 2018-08-13 18:24:35 -0700 (Mon, 13 Aug 2018) | 17 lines
[BasicAA] Don't assume tail calls with byval don't alias allocas
Summary:
Calls marked 'tail' cannot read or write allocas from the current frame
because the current frame might be destroyed by the time they run.
However, a tail call may use an alloca with byval. Calling with byval
copies the contents of the alloca into argument registers or stack
slots, so there is no lifetime issue. Tail calls never modify allocas,
so we can return just ModRefInfo::Ref.
Fixes PR38466, a longstanding bug.
Reviewers: hfinkel, nlewycky, gbiv, george.burgess.iv
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D50679
------------------------------------------------------------------------
llvm-svn: 339698
Diffstat (limited to 'llvm/lib/CodeGen/MacroFusion.cpp')
0 files changed, 0 insertions, 0 deletions
