Commit Graph

11 Commits

Author SHA1 Message Date
Evan Cheng 65f9d19c4f Re-commit r151623 with fix. Only issue special no-return calls if it's a direct call.
llvm-svn: 151645
2012-02-28 18:51:51 +00:00
Daniel Dunbar ee7b899343 Revert r151623 "Some ARM implementaions, e.g. A-series, does return stack prediction. ...", it is breaking the Clang build during the Compiler-RT part.
llvm-svn: 151630
2012-02-28 15:36:07 +00:00
Evan Cheng 87c7b09d8d Some ARM implementaions, e.g. A-series, does return stack prediction. That is,
the processor keeps a return addresses stack (RAS) which stores the address
and the instruction execution state of the instruction after a function-call
type branch instruction.

Calling a "noreturn" function with normal call instructions (e.g. bl) can
corrupt RAS and causes 100% return misprediction so LLVM should use a
unconditional branch instead. i.e.
mov lr, pc
b _foo
The "mov lr, pc" is issued in order to get proper backtrace.

rdar://8979299

llvm-svn: 151623
2012-02-28 06:42:03 +00:00
Chris Lattner 229907cd11 land David Blaikie's patch to de-constify Type, with a few tweaks.
llvm-svn: 135375
2011-07-18 04:54:35 +00:00
Chris Lattner 0ab5e2cded Fix a ton of comment typos found by codespell. Patch by
Luis Felipe Strano Moraes!

llvm-svn: 129558
2011-04-15 05:18:47 +00:00
Chris Lattner 3e5fbd74ed rename MVT::Flag to MVT::Glue. "Flag" is a terrible name for
something that just glues two nodes together, even if it is
sometimes used for flags.

llvm-svn: 122310
2010-12-21 02:38:05 +00:00
Duncan Sands 98512315f7 When passing a huge parameter using the byval mechanism, a long
sequence of loads and stores was being generated to perform the
copy on the x86 targets if the parameter was less than 4 byte
aligned, causing llc to use up vast amounts of memory and time.
Use a "rep movs" form instead.  PR7170.

llvm-svn: 118260
2010-11-04 21:16:46 +00:00
Chris Lattner 4470c2bb23 Fix a bug where the x86 backend would lower memcpy/memset of segment relative operations
into non-segment-relative copies.

llvm-svn: 114402
2010-09-21 05:43:34 +00:00
Chris Lattner 2510de2bea reimplement memcpy/memmove/memset lowering to use MachinePointerInfo
instead of srcvalue/offset pairs.  This corrects SV info for mem 
operations whose size is > 32-bits.

llvm-svn: 114401
2010-09-21 05:40:29 +00:00
Dan Gohman bb919dfb6b Implement a bunch more TargetSelectionDAGInfo infrastructure.
Move EmitTargetCodeForMemcpy, EmitTargetCodeForMemset, and
EmitTargetCodeForMemmove out of TargetLowering and into
SelectionDAGInfo to exercise this.

llvm-svn: 103481
2010-05-11 17:31:57 +00:00
Dan Gohman 9becdddc49 Add skeleton target-specific SelectionDAGInfo files.
llvm-svn: 101564
2010-04-16 23:04:22 +00:00