Redundant bound check "(uint)c > 'f' ? 0xFF : CharToHexLookup[c]" #81160
Description
Bound check is not eliminated in the following snippet (from #81146 (comment)):
static int Test(char c) => FromChar_UInt_GT(c);
static int FromChar_UInt_GT(int c) => (uint)c > 'f' ? 0xFF : CharToHexLookup[c];
static ReadOnlySpan<byte> CharToHexLookup => new byte[]
{
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 15
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 31
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 47
0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 63
0xFF, 0xA, 0xB, 0xC, 0xD, 0xE, 0xF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 79
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 95
0xFF, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 111
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 127
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 143
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 159
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 175
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 191
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 207
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 223
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 239
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF // 255
};Codegen for Test()
; Method C:Test(ushort):int
G_M31930_IG01: ;; offset=0000H
4883EC28 sub rsp, 40
;; size=4 bbWeight=1 PerfScore 0.25
G_M31930_IG02: ;; offset=0004H
0FB7C1 movzx rax, cx
83F866 cmp eax, 102
7719 ja SHORT G_M31930_IG04
;; size=8 bbWeight=1 PerfScore 1.50
G_M31930_IG03: ;; offset=000CH
3D00010000 cmp eax, 256
731C jae SHORT G_M31930_IG06
8BC0 mov eax, eax
48BA102C824E09020000 mov rdx, 0x2094E822C10 ; static handle
0FB60410 movzx rax, byte ptr [rax+rdx]
EB05 jmp SHORT G_M31930_IG05
;; size=25 bbWeight=0.50 PerfScore 2.88
G_M31930_IG04: ;; offset=0025H
B8FF000000 mov eax, 255
;; size=5 bbWeight=0.50 PerfScore 0.12
G_M31930_IG05: ;; offset=002AH
4883C428 add rsp, 40
C3 ret
;; size=5 bbWeight=1 PerfScore 1.25
G_M31930_IG06: ;; offset=002FH
E8BCA8495F call CORINFO_HELP_RNGCHKFAIL
CC int3
;; size=6 bbWeight=0 PerfScore 0.00
; Total bytes of code: 53