to know about calls that cannot throw ('nounwind'):
if such a call does throw for some reason then the
personality will terminate the program. The distinction
between an ordinary call and a nounwind call is that
an ordinary call gets an entry in the exception table
but a nounwind call does not. This patch sets up the
exception table appropriately. One oddity is that
I've chosen to bracket nounwind calls with labels (like
invokes) - the other choice would have been to bracket
ordinary calls with labels. While bracketing
ordinary calls is more natural (because bracketing
by labels would then correspond exactly to getting an
entry in the exception table), I didn't do it because
introducing labels impedes some optimizations and I'm
guessing that ordinary calls occur more often than
nounwind calls. This fixes the gcc filter2 eh test,
at least at -O0 (the inliner needs some tweaking at
higher optimization levels).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45197 91177308-0d34-0410-b5e6-96231b3b80d8
how to lower them (with no attempt made to be
efficient, since they should only occur for
unoptimized code).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45108 91177308-0d34-0410-b5e6-96231b3b80d8
SelectionDAG::getConstant, in the same way as vector floating-point
constants. This allows the legalize expansion code for @llvm.ctpop and
friends to be usable with vector types.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44954 91177308-0d34-0410-b5e6-96231b3b80d8
_foo:
movl $12, %eax
andl 4(%esp), %eax
movl _array(%eax), %eax
ret
instead of:
_foo:
movl 4(%esp), %eax
shrl $2, %eax
andl $3, %eax
movl _array(,%eax,4), %eax
ret
As it turns out, this triggers all the time, in a wide variety of
situations, for example, I see diffs like this in various programs:
- movl 8(%eax), %eax
- shll $2, %eax
- andl $1020, %eax
- movl (%esi,%eax), %eax
+ movzbl 8(%eax), %eax
+ movl (%esi,%eax,4), %eax
- shll $2, %edx
- andl $1020, %edx
- movl (%edi,%edx), %edx
+ andl $255, %edx
+ movl (%edi,%edx,4), %edx
Unfortunately, I also see stuff like this, which can be fixed in the
X86 backend:
- andl $85, %ebx
- addl _bit_count(,%ebx,4), %ebp
+ shll $2, %ebx
+ andl $340, %ebx
+ addl _bit_count(%ebx), %ebp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44656 91177308-0d34-0410-b5e6-96231b3b80d8
throw exceptions", just mark intrinsics with the nounwind
attribute. Likewise, mark intrinsics as readnone/readonly
and get rid of special aliasing logic (which didn't use
anything more than this anyway).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44544 91177308-0d34-0410-b5e6-96231b3b80d8
the function type, instead they belong to functions
and function calls. This is an updated and slightly
corrected version of Reid Spencer's original patch.
The only known problem is that auto-upgrading of
bitcode files doesn't seem to work properly (see
test/Bitcode/AutoUpgradeIntrinsics.ll). Hopefully
a bitcode guru (who might that be? :) ) will fix it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44359 91177308-0d34-0410-b5e6-96231b3b80d8
optimized. This avoids creating illegal divisions when the combiner is
running after legalize; this fixes PR1815. Also, it produces better
code in the included testcase by avoiding the subtract and multiply
when the division isn't optimized.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44341 91177308-0d34-0410-b5e6-96231b3b80d8
Improve a comment.
Unbreak Duncan's carefully written path compression where I didn't realize
what was happening!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44301 91177308-0d34-0410-b5e6-96231b3b80d8