C is a constant which can be sign-extended from 8 bits without value loss,
and op is one of: add, sub, imul, and, or, xor.
This allows the JIT to emit the one byte version of the constant instead of
the two or 4 byte version. Because these instructions are very common, this
can save a LOT of code space. For example, I sampled two benchmarks, 176.gcc
and 254.gap.
BM Old New Reduction
176.gcc 2673621 2548962 4.89%
254.gap 498261 475104 4.87%
Note that while the percentage is not spectacular, this did eliminate
124.6 _KILOBYTES_ of codespace from gcc. Not bad.
Note that this doesn't effect the llc version at all, because the assembler
already does this optimization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9284 91177308-0d34-0410-b5e6-96231b3b80d8
* Implement R1 = R2 * C where R1 and R2 are 32 or 16 bits. This avoids an
extra copy into a register, reducing register pressure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9278 91177308-0d34-0410-b5e6-96231b3b80d8
getelementptr code path for use by other code paths (like malloc and alloca).
* Optimize comparisons with zero
* Generate neg, not, inc, and dec instructions, when possible.
This gives some code size wins, which might translate into performance. We'll
see tommorow in the nightly tester.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9267 91177308-0d34-0410-b5e6-96231b3b80d8
X86/linux. :( The problem is that a signal delivered while the function
is executing could clobber the functions stack. This is a partial fix
for PR41.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9113 91177308-0d34-0410-b5e6-96231b3b80d8
much cleaner and easier.
Labeled .td as a suffix for tblgen files in Makefile.rules.
Modified build rules so that source files generated during the build are placed
in the build directory and not the source directory (and not in a Debug
directory). This makes the system cleaner and allows us to have a read-only
source tree.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8424 91177308-0d34-0410-b5e6-96231b3b80d8
into the struct case.
* Extend printConstantValueOnly to print .zero's if the initializer is zero
* Delete dead isConstantFunctionPointerRef function
* Emit the appropriate assembly for the various linkage types!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8417 91177308-0d34-0410-b5e6-96231b3b80d8
Adjusted Makefile to work with new autoconf-style object root.
Specifically, use the new -I option of tblgen to find include files.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8379 91177308-0d34-0410-b5e6-96231b3b80d8
until we implement unwinding.
Add support for the invoke instruction, which codegens just like a call with
a branch after it.
The end effect of this change is that programs using the invoke instruction,
but never unwinding, will work fine. Programs that unwind will abort until
we get unwind support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8187 91177308-0d34-0410-b5e6-96231b3b80d8
This bug caused miscompilation of programs using 'struct stat', but only if
compiled with support for 64-bit filesystems. This could in theory effect
other things, but only if the LLVM code shared data structures with native code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7928 91177308-0d34-0410-b5e6-96231b3b80d8
