Chris Lattner 0ea26ca45b Expand 64-bit shifts more optimally if we know that the high bit of the ... 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		2006-09-20 03:38:48 +00:00
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Analysis	Explain change with a comment.	2006-09-17 17:51:00 +00:00
Archive
AsmParser	Added some eye-candy for Subtarget type checking	2006-09-17 20:25:45 +00:00
Bytecode
CodeGen	Expand 64-bit shifts more optimally if we know that the high bit of the	2006-09-20 03:38:48 +00:00
Debugger
ExecutionEngine
Linker
Support
System
Target	fix header	2006-09-19 16:41:40 +00:00
Transforms	Back out Chris' last set of changes. This breaks 177.mesa and povray somehow.	2006-09-20 01:39:40 +00:00
VMCore	add a helper method	2006-09-18 04:54:57 +00:00
Makefile