Issue #894: trap on floating-point ops with reserved rounding modes: detect Zfa flt

This commit is contained in:
David Harris 2024-07-25 09:09:13 -07:00
parent f7dd49cc6c
commit 5bf7250687

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@ -95,8 +95,11 @@ module fctrl import cvw::*; #(parameter cvw_t P) (
assign SupportedFmt2 = (Fmt2 == 2'b00 | (Fmt2 == 2'b01 & P.D_SUPPORTED) |
(Fmt2 == 2'b10 & P.ZFH_SUPPORTED) | (Fmt2 == 2'b11 & P.Q_SUPPORTED));
// rounding modes 5 and 6 are reserved. Rounding mode 7 is dynamic, and is reserved if FRM is 5, 6, or 7
assign SupportedRM = ~(Funct3D == 3'b101 | Funct3D == 3'b110 | (Funct3D == 3'b111 & (FRM_REGW == 3'b101 | FRM_REGW == 3'b110 | FRM_REGW == 3'b111)));
assign SupportedRM = ~(Funct3D == 3'b101 | Funct3D == 3'b110 | (Funct3D == 3'b111 & (FRM_REGW == 3'b101 | FRM_REGW == 3'b110 | FRM_REGW == 3'b111))) |
(OpD == 7'b1010011 & Funct3D == 3'b101 & Funct7D[6:2] == 5'b10100 & P.ZFA_SUPPORTED); // Zfa fltq has a funny rounding mode
/*assign SupportedRM = ~(Funct3D == 3'b101 | Funct3D == 3'b110 | (Funct3D == 3'b111 & (FRM_REGW == 3'b101 | FRM_REGW == 3'b110 | FRM_REGW == 3'b111))) |
(OpD == 7'b1010011 & P.ZFA_SUPPORTED);
*/
// decode the instruction
// FRegWrite_FWriteInt_FResSel_PostProcSel_FOpCtrl_FDivStart_IllegalFPUInstr_FCvtInt_Zfa_FroundNX
always_comb