Interleave IV simplifications. Currently involves EliminateComparison
and EliminateRemainder. Next I'll add EliminateExtend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131210 91177308-0d34-0410-b5e6-96231b3b80d8
return the pointer being dereferenced, it returns the pointee, but a call
might return the pointer itself.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130979 91177308-0d34-0410-b5e6-96231b3b80d8
This adds functionality to remove size/zero extension during indvars
without generating a canonical IV and rewriting all IV users. It's
disabled by default so should have no effect on codegen. Work in progress.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130829 91177308-0d34-0410-b5e6-96231b3b80d8
Only create a canonical IV for backedge taken count if it will
actually be used by LinearFunctionTestReplace. And some related
cleanup, preparing to reduce dependence on canonical IVs.
No significant effect on x86 or arm in the test-suite.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130799 91177308-0d34-0410-b5e6-96231b3b80d8
model constants which can be added to base registers via add-immediate
instructions which don't require an additional register to materialize
the immediate.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130743 91177308-0d34-0410-b5e6-96231b3b80d8
This automagically provides a transform noticed by my super-optimizer
as occurring quite often: "rem x, (select cond, x, 1)" -> 0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130694 91177308-0d34-0410-b5e6-96231b3b80d8
This obviously helps a lot if the division would be turned into a libcall
(think i64 udiv on i386), but div is also one of the few remaining instructions
on modern CPUs that become more expensive when the bitwidth gets bigger.
This also helps register pressure on i386 when dividing chars, divb needs
two 8-bit parts of a 16 bit register as input where divl uses two registers.
int foo(unsigned char a) { return a/10; }
int bar(unsigned char a, unsigned char b) { return a/b; }
compiles into (x86_64)
_foo:
imull $205, %edi, %eax
shrl $11, %eax
ret
_bar:
movzbl %dil, %eax
divb %sil, %al
movzbl %al, %eax
ret
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130615 91177308-0d34-0410-b5e6-96231b3b80d8
This shouldn't happen in practice because the icmp would be a constant.
Add a check so we don't miscompile code if something goes wrong.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130446 91177308-0d34-0410-b5e6-96231b3b80d8
between two reads (threading).
Fix an off-by-one in the indirect counter table that I meant to revert after an
earlier experiment. Whoops!
Implement GCOV_PREFIX. Doesn't handle GCOV_PREFIX_STRIP yet.
Fix an off-by-one in string emission. Extra whoops!
Tolerate DISubprograms that have null Function*'s attached to them. I don't yet
understand what this means, but it happens when you have a global static with
a non-trivial constructor/destructor.
Fix a crash on switch statements with a single successor (default-only).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130443 91177308-0d34-0410-b5e6-96231b3b80d8
a nice and tidy:
%x1 = load i32* %0, align 4
%1 = icmp eq i32 %x1, 1179403647
br i1 %1, label %if.then, label %if.end
instead of doing lots of loads and branches. May the FreeBSD bootloader
long fit in its allocated space.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130416 91177308-0d34-0410-b5e6-96231b3b80d8
