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https://github.com/c64scene-ar/llvm-6502.git
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Chris Lattner
b48da39536
the new TLI that is available.
Implement support for handling out of range shifts. This allows us to
compile this code (a 64-bit rotate):
unsigned long long f3(unsigned long long x) {
return (x << 32) | (x >> (64-32));
}
into this:
f3:
mov %EDX, DWORD PTR [%ESP + 4]
mov %EAX, DWORD PTR [%ESP + 8]
ret
GCC produces this:
$ gcc t.c -masm=intel -O3 -S -o - -fomit-frame-pointer
..
f3:
push %ebx
mov %ebx, DWORD PTR [%esp+12]
mov %ecx, DWORD PTR [%esp+8]
mov %eax, %ebx
mov %edx, %ecx
pop %ebx
ret
The Simple ISEL produces (eww gross):
f3:
sub %ESP, 4
mov DWORD PTR [%ESP], %ESI
mov %EDX, DWORD PTR [%ESP + 8]
mov %ECX, DWORD PTR [%ESP + 12]
mov %EAX, 0
mov %ESI, 0
or %EAX, %ECX
or %EDX, %ESI
mov %ESI, DWORD PTR [%ESP]
add %ESP, 4
ret
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19780 91177308-0d34-0410-b5e6-96231b3b80d8
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