We do not want to emit "Loop: ... brcond Out; br Loop", as it adds an extra
instruction in the loop. Instead, invert the condition and emit
"Loop: ... br!cond Loop; br Out.
Generalize the fix by moving it from PPCDAGToDAGISel to SelectionDAGLowering.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26231 91177308-0d34-0410-b5e6-96231b3b80d8
want to copy the files when the .cpp file changes, we want to copy them
to the .cvs versions when the .l/.y file change (like the comments even say).
This avoids having bogus changes show up in diffs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26229 91177308-0d34-0410-b5e6-96231b3b80d8
transfer.
According to the Intel P4 Optimization Manual:
Moves that write a portion of a register can introduce unwanted
dependences. The movsd reg, reg instruction writes only the bottom
64 bits of a register, not to all 128 bits. This introduces a dependence on
the preceding instruction that produces the upper 64 bits (even if those
bits are not longer wanted). The dependence inhibits register renaming,
and thereby reduces parallelism.
Not to mention movaps is shorter than movss.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26226 91177308-0d34-0410-b5e6-96231b3b80d8
Turns them into calls to memset / memcpy if 1) buffer(s) are not DWORD aligned,
2) size is not known to be greater or equal to some minimum value (currently 128).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26224 91177308-0d34-0410-b5e6-96231b3b80d8
unswitch this loop on 2 before sweating to unswitch on 1/3.
void test4(int N, int i, int C, int*P, int*Q) {
int j;
for (j = 0; j < N; ++j) {
switch (C) { // general unswitching.
default: P[i+j] = 0; break;
case 1: Q[i+j] = 0; break;
case 3: P[i+j] = Q[i+j]; break;
case 2: break; // TRIVIAL UNSWITCH on C==2
}
}
}
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26223 91177308-0d34-0410-b5e6-96231b3b80d8
this for example:
for (j = 0; j < N; ++j) { // trivial unswitch
if (C)
P[i+j] = 0;
}
turning it into the obvious code without bothering to duplicate an empty loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26220 91177308-0d34-0410-b5e6-96231b3b80d8
like the flex stuff, which actually works when people do cvs updates and
get conflicts in the updated checked in file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26205 91177308-0d34-0410-b5e6-96231b3b80d8
it, because this:
.bss
X:
.byte 0
results in the assembler warning: "initialization in bss segment". Annoying.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26204 91177308-0d34-0410-b5e6-96231b3b80d8
The ABI specifies that there is a register save area at the bottom of the
stack, which means the actual used pointer needs to be an offset from
the subtracted value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26202 91177308-0d34-0410-b5e6-96231b3b80d8
GCC's syntax for auto-dependency generation stuff. This should
be changed to be disabling dependency stuff unless GCC/ICC is
found.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26201 91177308-0d34-0410-b5e6-96231b3b80d8
go through, but we do want to know if we're using GCC/ICC since they
share certain funky command line options (for dependency generation
stuff)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26198 91177308-0d34-0410-b5e6-96231b3b80d8
emit it (instead of .space), saving a bit of space in the .o file.
For example:
int foo[100];
int bar[100] = {};
when compiled with C++ or -fno-common results in shrinkage from 1160 to 360
bytes of space. The X86 backend can also do this on darwin.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26185 91177308-0d34-0410-b5e6-96231b3b80d8
