[SimplifyCFG] Fix illegal-width bitmap from switch lookup table#8444
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[SimplifyCFG] Fix illegal-width bitmap from switch lookup table#8444damyanp wants to merge 1 commit into
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…osoft#8421) SwitchLookupTable built bitmap APInts of width `TableSize * ResultBitWidth`, producing non-standard integer widths (i9, i17, i26, i33, i40, ...) that DXIL validation rejects - DXIL only allows i1/i8/i16/i32/i64. Round the bitmap width up to a legal width, and cap the optimization at 32 bits to avoid silently promoting to i64 (which would set the Int64Ops shader flag and add a 64-bit-integer capability requirement the source shader did not have). Wider tables fall back to the array path, or - for i1 results - preserve the original switch. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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SwitchLookupTable built bitmap APInts of width
TableSize * ResultBitWidth, producing non-standard integer widths (i9, i17, i26, i33, i40, ...) that DXIL validation rejects - DXIL only allows i1/i8/i16/i32/i64.Round the bitmap width up to a legal width, and cap the optimization at 32 bits to avoid silently promoting to i64 (which would set the Int64Ops shader flag and add a 64-bit-integer capability requirement the source shader did not have). Wider tables fall back to the array path, or - for i1 results - preserve the original switch.
Closes #8421
Co-authored-by: Copilot 223556219+Copilot@users.noreply.github.com