BuildSchedGraph was quadratic in the number of calls in the basic
block. After this fix, it keeps only a single call at the top of the
DefList so compile time doesn't blow up on large blocks. This reduces
postRA sched time on an external test case from 81s to 0.3s. Although
r130800 (reduced ARM register alias defs) also partially fixes the
issue by reducing the constant overhead of checking call interference
by an order of magnitude.
Fixes <rdar://problem/7662664> very poor compile time with post RA scheduling.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130943 91177308-0d34-0410-b5e6-96231b3b80d8
I tested both gdb on a bootstrapped clang and and the gdb testsuite on OS X (snow leopard)
and both are happy using __eh_frame.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130937 91177308-0d34-0410-b5e6-96231b3b80d8
who used this flag, and it now emits CFI and doesn't emit this anymore. All
other targets left this flag "false".
<rdar://problem/8486371>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130918 91177308-0d34-0410-b5e6-96231b3b80d8
Joining physregs is inherently dangerous because it uses a heuristic to avoid
creating invalid code. Linear scan had an emergency spilling mechanism to deal
with those rare cases. The new greedy allocator does not.
The greedy register allocator is much better at taking hints, so this has almost
no impact on code size and quality. The few cases where it matters show up as
unit tests that now have -join-physregs enabled explicitly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130896 91177308-0d34-0410-b5e6-96231b3b80d8
It is OK for B to be any GR8_ABCD_H superclass, the returned register class
doesn't have to map surjectively onto B.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130892 91177308-0d34-0410-b5e6-96231b3b80d8
Most of these tests require a single mov instruction that can come either before
or after a 2-addr instruction. -join-physregs changes the behavior, but the
results are equivalent.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130891 91177308-0d34-0410-b5e6-96231b3b80d8
landing pad as its successor.
SjLj exception handling jumps to the correct landing pad via a switch statement
that's generated right before code-gen. Loosen the constraint in the machine
instruction verifier to allow for this. Note, this isn't the most rigorous check
since we cannot determine where that switch statement came from. But it's
marginally better than turning this check off when SjLj exceptions are used.
<rdar://problem/9187612>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130881 91177308-0d34-0410-b5e6-96231b3b80d8
That's kinda weird because the .gcno files are supposed to already be there,
but libgcov does this and somehow Google has managed to depend on it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130879 91177308-0d34-0410-b5e6-96231b3b80d8
Original message:
Teach MachineCSE how to do simple cross-block CSE involving physregs. This allows, for example, eliminating duplicate cmpl's on x86. Part of rdar://problem/8259436 .
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130877 91177308-0d34-0410-b5e6-96231b3b80d8
These tests all follow the same pattern:
mov r2, r0
movs r0, #0
$CMP r2, r1
it eq
moveq r0, #1
bx lr
The first 'mov' can be eliminated by rematerializing 'movs r0, #0' below the
test instruction:
$CMP r0, r1
mov.w r0, #0
it eq
moveq r0, #1
bx lr
So far, only physreg coalescing can do that. The register allocators won't yet
split live ranges just to eliminate copies. They can learn, but this particular
problem is not likely to show up in real code. It only appears because r0 is
used for both the function argument and return value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130858 91177308-0d34-0410-b5e6-96231b3b80d8
