mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-04-05 17:39:16 +00:00
0ea26ca45b
shift amount is one or zero. For example, for:
long long foo1(long long X, int C) {
return X << (C|32);
}
long long foo2(long long X, int C) {
return X << (C&~32);
}
we get:
_foo1:
movb $31, %cl
movl 4(%esp), %edx
andb 12(%esp), %cl
shll %cl, %edx
xorl %eax, %eax
ret
_foo2:
movb $223, %cl
movl 4(%esp), %eax
movl 8(%esp), %edx
andb 12(%esp), %cl
shldl %cl, %eax, %edx
shll %cl, %eax
ret
instead of:
_foo1:
subl $4, %esp
movl %ebx, (%esp)
movb $32, %bl
movl 8(%esp), %eax
movl 12(%esp), %edx
movb %bl, %cl
orb 16(%esp), %cl
shldl %cl, %eax, %edx
shll %cl, %eax
xorl %ecx, %ecx
testb %bl, %bl
cmovne %eax, %edx
cmovne %ecx, %eax
movl (%esp), %ebx
addl $4, %esp
ret
_foo2:
subl $4, %esp
movl %ebx, (%esp)
movb $223, %cl
movl 8(%esp), %eax
movl 12(%esp), %edx
andb 16(%esp), %cl
shldl %cl, %eax, %edx
shll %cl, %eax
xorl %ecx, %ecx
xorb %bl, %bl
testb %bl, %bl
cmovne %eax, %edx
cmovne %ecx, %eax
movl (%esp), %ebx
addl $4, %esp
ret
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30506 91177308-0d34-0410-b5e6-96231b3b80d8
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.