[llvm] [DAG] Generalize fold (not (neg x)) -> (add X, -1) (PR #154348)

[Simon Pilgrim via llvm-commits]

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@@ -896,12 +896,12 @@ define i64 @opaque_constant(i1 %cond, i64 %x) {
 ; X86-NEXT:    movl {{[0-9]+}}(%esp), %ecx
 ; X86-NEXT:    movl {{[0-9]+}}(%esp), %esi
 ; X86-NEXT:    movzbl {{[0-9]+}}(%esp), %eax
-; X86-NEXT:    movl %eax, %edx
-; X86-NEXT:    andl $1, %edx
-; X86-NEXT:    negl %edx
-; X86-NEXT:    andl $1, %edx
-; X86-NEXT:    decl %eax
-; X86-NEXT:    andl $1, %eax
+; X86-NEXT:    andl	$1, %eax
+; X86-NEXT:    negl	%eax
+; X86-NEXT:    movl	%eax, %edx
+; X86-NEXT:    andl	$1, %edx
+; X86-NEXT:    notl	%eax
+; X86-NEXT:    andl	$1, %eax
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RKSimon wrote:

why is there a diff on seemingly identical lines? weird whitespace change? 

https://github.com/llvm/llvm-project/pull/154348