- This works, but won't handle crashes on stack overflow, or signals delivered
to a thread other than the one that crashed. The latter is particular annoying
on Darwin, because SIGABRT tends to go to the main thread.
llvm-svn: 109717
- Designed as a simple wrapper to allow clients to attempt to catch crashes
(memory errors, assertion violations, etc.) and do some kind of recovery.
- Currently doesn't actually attempt to catch crashes.
llvm-svn: 109586
replaced by a bigger array in SmallPtrSet (by overridding it), instead just use a
pointer to the start of the storage, and have SmallPtrSet pass in the value to use.
This has the disadvantage that SmallPtrSet becomes bigger by one pointer. It has
the advantage that it no longer uses tricky C++ rules, and is clearly correct while
I'm not sure the previous version was. This was inspired by g++-4.6 pointing out
that SmallPtrSetImpl was writing off the end of SmallArray, which it was. Since
SmallArray is replaced with a bigger array in SmallPtrSet, the write was still to
valid memory. But it was writing off the end of the declared array type - sounds
kind of dubious to me, like it sounded dubious to g++-4.6. Maybe g++-4.6 is wrong
and this construct is perfectly valid and correctly compiled by all compilers, but
I think it is better to avoid the whole can of worms by avoiding this construct.
llvm-svn: 107285
buffer in the same chunk of memory.
2 less mallocs for every uninitialized MemoryBuffer and 1 less malloc for every
MemoryBuffer pointing to a memory range translate into 20% less mallocs on
clang -cc1 -Eonly Cocoa_h.m.
llvm-svn: 106839
switch from this:
if (TimePassesIsEnabled) {
NamedRegionTimer T(Name, GroupName);
do_something();
} else {
do_something(); // duplicate the code, this time without a timer!
}
to this:
{
NamedRegionTimer T(Name, GroupName, TimePassesIsEnabled);
do_something();
}
llvm-svn: 106285
EAGAIN and EWOULDBLOCK are used here.
Also, handle the case where a write call is interrupted after
some data has already been written.
llvm-svn: 103153
Microoptimize Twine's with unsigned and int to not pin their value to
the stack. This saves stack space in common cases and allows mem2reg
in the caller. A simple example is:
void foo(const Twine &);
void bar(int x) {
foo("xyz: " + Twine(x));
}
Before:
__Z3bari:
subq $40, %rsp
movl %edi, 36(%rsp)
leaq L_.str3(%rip), %rax
leaq 36(%rsp), %rcx
leaq 8(%rsp), %rdi
movq %rax, 8(%rsp)
movq %rcx, 16(%rsp)
movb $3, 24(%rsp)
movb $7, 25(%rsp)
callq __Z3fooRKN4llvm5TwineE
addq $40, %rsp
ret
After:
__Z3bari:
subq $24, %rsp
leaq L_.str3(%rip), %rax
movq %rax, (%rsp)
movslq %edi, %rax
movq %rax, 8(%rsp)
movb $3, 16(%rsp)
movb $7, 17(%rsp)
leaq (%rsp), %rdi
callq __Z3fooRKN4llvm5TwineE
addq $24, %rsp
ret
It saves 16 bytes of stack and one instruction in this case.
llvm-svn: 103107
We have some code in llvm and clang where a BumpPtrAllocator is declared in a
class but never used in the common case. Stop wasting memory there.
llvm-svn: 101130
