[RISCV] Add hasSideEffects = true to ReadFRM

futog · futog · commit 240ec097e9ed · 2025-05-14T11:06:41.000+02:00
ReadFRM should not be optimized out.
diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfo.td b/llvm/lib/Target/RISCV/RISCVInstrInfo.td
@@ -2006,7 +2006,9 @@ class SwapSysRegImm<SysReg SR, list<Register> Regs>
   let Defs = Regs;
 }
 
+let hasSideEffects = true in
 def ReadFRM : ReadSysReg<SysRegFRM, [FRM]>;
+
 let hasPostISelHook = 1 in {
 def WriteFRM : WriteSysReg<SysRegFRM, [FRM]>;
 def WriteFRMImm : WriteSysRegImm<SysRegFRM, [FRM]>;

Original file line number	Diff line number	Diff line change
`@@ -2006,7 +2006,9 @@ class SwapSysRegImm<SysReg SR, list<Register> Regs>`
`2006`	`2006`	`let Defs = Regs;`
`2007`	`2007`	`}`
`2008`	`2008`
	`2009`	`+let hasSideEffects = true in`
`2009`	`2010`	`def ReadFRM : ReadSysReg<SysRegFRM, [FRM]>;`
	`2011`	`+`
`2010`	`2012`	`let hasPostISelHook = 1 in {`
`2011`	`2013`	`def WriteFRM : WriteSysReg<SysRegFRM, [FRM]>;`
`2012`	`2014`	`def WriteFRMImm : WriteSysRegImm<SysRegFRM, [FRM]>;`