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LLVM backend for 6502
XMM registers. There are many known deficiencies and fixmes, which will be addressed ASAP. The major benefit of this work is that it will allow the LLVM register allocator to allocate FP registers across basic blocks. The x86 backend will still default to x87 style FP. To enable this work, you must pass -enable-sse-scalar-fp and either -sse2 or -sse3 to llc. An example before and after would be for: double foo(double *P) { double Sum = 0; int i; for (i = 0; i < 1000; ++i) Sum += P[i]; return Sum; } The inner loop looks like the following: x87: .LBB_foo_1: # no_exit fldl (%esp) faddl (%eax,%ecx,8) fstpl (%esp) incl %ecx cmpl $1000, %ecx #FP_REG_KILL jne .LBB_foo_1 # no_exit SSE2: addsd (%eax,%ecx,8), %xmm0 incl %ecx cmpl $1000, %ecx #FP_REG_KILL jne .LBB_foo_1 # no_exit git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22340 91177308-0d34-0410-b5e6-96231b3b80d8 |
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autoconf | ||
docs | ||
examples | ||
include/llvm | ||
lib | ||
projects | ||
runtime | ||
test | ||
tools | ||
utils | ||
win32 | ||
.cvsignore | ||
configure | ||
CREDITS.TXT | ||
LICENSE.TXT | ||
llvm.spec | ||
llvm.spec.in | ||
Makefile | ||
Makefile.common | ||
Makefile.config.in | ||
Makefile.rules | ||
README.txt |
Low Level Virtual Machine (LLVM) ================================ This directory and its subdirectories contain source code for the Low Level Virtual Machine, a toolkit for the construction of highly optimized compilers, optimizers, and runtime environments. LLVM is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. Please see the HTML documentation provided in docs/index.html for further assistance with LLVM.