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llvm-project/llvm/test/CodeGen/X86/iabs.ll

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X86: optimize generated code for integer ABS This patch will generate the following for integer ABS: movl %edi, %eax negl %eax cmovll %edi, %eax INSTEAD OF movl %edi, %ecx sarl $31, %ecx leal (%rdi,%rcx), %eax xorl %ecx, %eax There exists a target-independent DAG combine for integer ABS, which converts integer ABS to sar+add+xor. For X86, we match this pattern back to neg+cmov. This is implemented in PerformXorCombine. rdar://10695237 llvm-svn: 158175
2012-06-08 06:39:10 +08:00
; RUN: llc < %s -march=x86-64 | FileCheck %s
new testcases for integer abs function llvm-svn: 35880
2007-04-11 13:02:57 +08:00
;; Integer absolute value, should produce something at least as good as:
X86: optimize generated code for integer ABS This patch will generate the following for integer ABS: movl %edi, %eax negl %eax cmovll %edi, %eax INSTEAD OF movl %edi, %ecx sarl $31, %ecx leal (%rdi,%rcx), %eax xorl %ecx, %eax There exists a target-independent DAG combine for integer ABS, which converts integer ABS to sar+add+xor. For X86, we match this pattern back to neg+cmov. This is implemented in PerformXorCombine. rdar://10695237 llvm-svn: 158175
2012-06-08 06:39:10 +08:00
;; movl %edi, %eax
;; negl %eax
;; cmovll %edi, %eax
new testcases for integer abs function llvm-svn: 35880
2007-04-11 13:02:57 +08:00
;; ret
X86: optimize generated code for integer ABS This patch will generate the following for integer ABS: movl %edi, %eax negl %eax cmovll %edi, %eax INSTEAD OF movl %edi, %ecx sarl $31, %ecx leal (%rdi,%rcx), %eax xorl %ecx, %eax There exists a target-independent DAG combine for integer ABS, which converts integer ABS to sar+add+xor. For X86, we match this pattern back to neg+cmov. This is implemented in PerformXorCombine. rdar://10695237 llvm-svn: 158175
2012-06-08 06:39:10 +08:00
; rdar://10695237
Mark functions in some tests as 'nounwind'. Generating EH info for these functions causes the tests to fail for random reasons (e.g. looking for 'or' or counting lines with asm-printer; labels count as lines.) llvm-svn: 49003
2008-04-01 07:20:09 +08:00
define i32 @test(i32 %a) nounwind {
X86: optimize generated code for integer ABS This patch will generate the following for integer ABS: movl %edi, %eax negl %eax cmovll %edi, %eax INSTEAD OF movl %edi, %ecx sarl $31, %ecx leal (%rdi,%rcx), %eax xorl %ecx, %eax There exists a target-independent DAG combine for integer ABS, which converts integer ABS to sar+add+xor. For X86, we match this pattern back to neg+cmov. This is implemented in PerformXorCombine. rdar://10695237 llvm-svn: 158175
2012-06-08 06:39:10 +08:00
; CHECK: test:
; CHECK: mov
; CHECK-NEXT: neg
; CHECK-NEXT: cmov
; CHECK-NEXT: ret
new testcases for integer abs function llvm-svn: 35880
2007-04-11 13:02:57 +08:00
%tmp1neg = sub i32 0, %a
%b = icmp sgt i32 %a, -1
%abs = select i1 %b, i32 %a, i32 %tmp1neg
ret i32 %abs
}