%X = and Y, constantint
%Z = setcc %X, 0
instead of emitting:
and %EAX, 3
test %EAX, %EAX
je .LBBfoo2_2 # UnifiedReturnBlock
We now emit:
test %EAX, 3
je .LBBfoo2_2 # UnifiedReturnBlock
This triggers 581 times on 176.gcc for example.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17080 91177308-0d34-0410-b5e6-96231b3b80d8
1. optional shift left
2. and x, immX
3. and y, immY
4. or z, x, y
==> rlwimi z, x, y, shift, mask begin, mask end
where immX == ~immY and immX is a run of set bits. This transformation
fires 32 times on voronoi, once on espresso, and probably several
dozen times on external benchmarks such as gcc.
To put this in terms of actual code generated for
struct B { unsigned a : 3; unsigned b : 2; };
void storeA (struct B *b, int v) { b->a = v;}
void storeB (struct B *b, int v) { b->b = v;}
Old:
_storeA:
rlwinm r2, r4, 0, 29, 31
lwz r4, 0(r3)
rlwinm r4, r4, 0, 0, 28
or r2, r4, r2
stw r2, 0(r3)
blr
_storeB:
rlwinm r2, r4, 3, 0, 28
rlwinm r2, r2, 0, 27, 28
lwz r4, 0(r3)
rlwinm r4, r4, 0, 29, 26
or r2, r2, r4
stw r2, 0(r3)
blr
New:
_storeA:
lwz r2, 0(r3)
rlwimi r2, r4, 0, 29, 31
stw r2, 0(r3)
blr
_storeB:
lwz r2, 0(r3)
rlwimi r2, r4, 3, 27, 28
stw r2, 0(r3)
blr
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17078 91177308-0d34-0410-b5e6-96231b3b80d8
flag rotate left word immediate then mask insert (rlwimi) as a two-address
instruction, and update the ISel usage of the instruction accordingly.
This will allow us to properly schedule rlwimi, and use it to efficiently
codegen bitfield operations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17068 91177308-0d34-0410-b5e6-96231b3b80d8
that the vtables for these classes are only instantiated in this translation
unit, not in every xlation unit they are used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17026 91177308-0d34-0410-b5e6-96231b3b80d8
case:
int C[100];
int foo() {
return C[4];
}
We now codegen:
foo:
mov %EAX, DWORD PTR [C + 16]
ret
instead of:
foo:
mov %EAX, OFFSET C
mov %EAX, DWORD PTR [%EAX + 16]
ret
Other impressive features may be coming later.
This patch is contributed by Jeff Cohen!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17011 91177308-0d34-0410-b5e6-96231b3b80d8
useful when you have a reference like:
int A[100];
void foo() { A[10] = 1; }
In this case, &A[10] is a single constant and should be treated as such.
Only MO_GlobalAddress and MO_ExternalSymbol are allowed to use this field, no
other operand type is.
This is another fine patch contributed by Jeff Cohen!!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17007 91177308-0d34-0410-b5e6-96231b3b80d8
The problem occurred when trying to reload this instruction:
MOV32mr %reg2326, 8, %reg2297, 4, %reg2295
The value of reg2326 was available in EBX, so it was reused from there, instead
of reloading it into EDX.
The value of reg2297 was available in EDX, so it was reused from there, instead
of reloading it into EDI.
The value of reg2295 was not available, so we tried reloading it into EBX, its
assigned register. However, we checked and saw that we already reloaded
something into EBX, so we chose what reg2326 was assigned to (EDX) and reloaded
into that register instead.
Unfortunately EDX had already been used by reg2297, so reloading into EDX
clobbered the value used by the reg2326 operand, breaking the program.
The fix for this is to check that the newly picked register is ok. In this
case we now find that EDX is already used and try using EDI, which succeeds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17006 91177308-0d34-0410-b5e6-96231b3b80d8
This transformation fires a few dozen times across the testsuite.
For example, int test2(int X) { return X ^ 0x0FF00FF0; }
Old:
_test2:
lis r2, 4080
ori r2, r2, 4080
xor r3, r3, r2
blr
New:
_test2:
xoris r3, r3, 4080
xori r3, r3, 4080
blr
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17004 91177308-0d34-0410-b5e6-96231b3b80d8
