[llvm] [DAG] Add computeKnownBits(FREEZE(X)) handling (PR #214095)

[Simon Pilgrim via llvm-commits]

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@@ -867,8 +867,10 @@ define i32 @freeze_ssubo(i32 %a0, i32 %a1, i8 %a2, i8 %a3) nounwind {
 ; X86:       # %bb.0:
 ; X86-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; X86-NEXT:    movzbl {{[0-9]+}}(%esp), %ecx
+; X86-NEXT:    xorl %edx, %edx
 ; X86-NEXT:    addb {{[0-9]+}}(%esp), %cl
-; X86-NEXT:    sbbl $0, %eax
+; X86-NEXT:    setb %dl
+; X86-NEXT:    subl %edx, %eax
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RKSimon wrote:

Have you investigated whats going on here?

https://github.com/llvm/llvm-project/pull/214095