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[RISCV] Disable zcmp push/pop for variadic functions. #65302

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Merged
merged 1 commit into from
Sep 11, 2023
Merged

[RISCV] Disable zcmp push/pop for variadic functions. #65302

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10 changes: 7 additions & 3 deletions llvm/lib/Target/RISCV/RISCVMachineFunctionInfo.h
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Original file line number Diff line number Diff line change
Expand Up @@ -128,9 +128,13 @@ class RISCVMachineFunctionInfo : public MachineFunctionInfo {
void setCalleeSavedStackSize(unsigned Size) { CalleeSavedStackSize = Size; }

bool isPushable(const MachineFunction &MF) const {
return (!useSaveRestoreLibCalls(MF) &&
MF.getSubtarget<RISCVSubtarget>().hasStdExtZcmp() &&
!MF.getTarget().Options.DisableFramePointerElim(MF));
// We cannot use fixed locations for the callee saved spill slots if the
// function uses a varargs save area.
// TODO: Use a seperate placement for vararg registers to enable Zcmp.
return !useSaveRestoreLibCalls(MF) &&
MF.getSubtarget<RISCVSubtarget>().hasStdExtZcmp() &&
!MF.getTarget().Options.DisableFramePointerElim(MF) &&
VarArgsSaveSize == 0;
}

int getRVPushRlist() const { return RVPushRlist; }
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176 changes: 176 additions & 0 deletions llvm/test/CodeGen/RISCV/callee-saved-gprs.ll
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Original file line number Diff line number Diff line change
Expand Up @@ -2127,3 +2127,179 @@ entry:
tail call void asm sideeffect "li s4, 0", "~{s4}"()
ret void
}

define void @varargs(...) {
; RV32I-LABEL: varargs:
; RV32I: # %bb.0:
; RV32I-NEXT: addi sp, sp, -48
; RV32I-NEXT: .cfi_def_cfa_offset 48
; RV32I-NEXT: sw ra, 12(sp) # 4-byte Folded Spill
; RV32I-NEXT: .cfi_offset ra, -36
; RV32I-NEXT: sw a7, 44(sp)
; RV32I-NEXT: sw a6, 40(sp)
; RV32I-NEXT: sw a5, 36(sp)
; RV32I-NEXT: sw a4, 32(sp)
; RV32I-NEXT: sw a3, 28(sp)
; RV32I-NEXT: sw a2, 24(sp)
; RV32I-NEXT: sw a1, 20(sp)
; RV32I-NEXT: sw a0, 16(sp)
; RV32I-NEXT: call callee@plt
; RV32I-NEXT: lw ra, 12(sp) # 4-byte Folded Reload
; RV32I-NEXT: addi sp, sp, 48
; RV32I-NEXT: ret
;
; RV32I-WITH-FP-LABEL: varargs:
; RV32I-WITH-FP: # %bb.0:
; RV32I-WITH-FP-NEXT: addi sp, sp, -48
; RV32I-WITH-FP-NEXT: .cfi_def_cfa_offset 48
; RV32I-WITH-FP-NEXT: sw ra, 12(sp) # 4-byte Folded Spill
; RV32I-WITH-FP-NEXT: sw s0, 8(sp) # 4-byte Folded Spill
; RV32I-WITH-FP-NEXT: .cfi_offset ra, -36
; RV32I-WITH-FP-NEXT: .cfi_offset s0, -40
; RV32I-WITH-FP-NEXT: addi s0, sp, 16
; RV32I-WITH-FP-NEXT: .cfi_def_cfa s0, 32
; RV32I-WITH-FP-NEXT: sw a7, 28(s0)
; RV32I-WITH-FP-NEXT: sw a6, 24(s0)
; RV32I-WITH-FP-NEXT: sw a5, 20(s0)
; RV32I-WITH-FP-NEXT: sw a4, 16(s0)
; RV32I-WITH-FP-NEXT: sw a3, 12(s0)
; RV32I-WITH-FP-NEXT: sw a2, 8(s0)
; RV32I-WITH-FP-NEXT: sw a1, 4(s0)
; RV32I-WITH-FP-NEXT: sw a0, 0(s0)
; RV32I-WITH-FP-NEXT: call callee@plt
; RV32I-WITH-FP-NEXT: lw ra, 12(sp) # 4-byte Folded Reload
; RV32I-WITH-FP-NEXT: lw s0, 8(sp) # 4-byte Folded Reload
; RV32I-WITH-FP-NEXT: addi sp, sp, 48
; RV32I-WITH-FP-NEXT: ret
;
; RV32IZCMP-LABEL: varargs:
; RV32IZCMP: # %bb.0:
; RV32IZCMP-NEXT: addi sp, sp, -48
; RV32IZCMP-NEXT: .cfi_def_cfa_offset 48
; RV32IZCMP-NEXT: sw ra, 12(sp) # 4-byte Folded Spill
; RV32IZCMP-NEXT: .cfi_offset ra, -36
; RV32IZCMP-NEXT: sw a7, 44(sp)
; RV32IZCMP-NEXT: sw a6, 40(sp)
; RV32IZCMP-NEXT: sw a5, 36(sp)
; RV32IZCMP-NEXT: sw a4, 32(sp)
; RV32IZCMP-NEXT: sw a3, 28(sp)
; RV32IZCMP-NEXT: sw a2, 24(sp)
; RV32IZCMP-NEXT: sw a1, 20(sp)
; RV32IZCMP-NEXT: sw a0, 16(sp)
; RV32IZCMP-NEXT: call callee@plt
; RV32IZCMP-NEXT: lw ra, 12(sp) # 4-byte Folded Reload
; RV32IZCMP-NEXT: addi sp, sp, 48
; RV32IZCMP-NEXT: ret
;
; RV32IZCMP-WITH-FP-LABEL: varargs:
; RV32IZCMP-WITH-FP: # %bb.0:
; RV32IZCMP-WITH-FP-NEXT: addi sp, sp, -48
; RV32IZCMP-WITH-FP-NEXT: .cfi_def_cfa_offset 48
; RV32IZCMP-WITH-FP-NEXT: sw ra, 12(sp) # 4-byte Folded Spill
; RV32IZCMP-WITH-FP-NEXT: sw s0, 8(sp) # 4-byte Folded Spill
; RV32IZCMP-WITH-FP-NEXT: .cfi_offset ra, -36
; RV32IZCMP-WITH-FP-NEXT: .cfi_offset s0, -40
; RV32IZCMP-WITH-FP-NEXT: addi s0, sp, 16
; RV32IZCMP-WITH-FP-NEXT: .cfi_def_cfa s0, 32
; RV32IZCMP-WITH-FP-NEXT: sw a7, 28(s0)
; RV32IZCMP-WITH-FP-NEXT: sw a6, 24(s0)
; RV32IZCMP-WITH-FP-NEXT: sw a5, 20(s0)
; RV32IZCMP-WITH-FP-NEXT: sw a4, 16(s0)
; RV32IZCMP-WITH-FP-NEXT: sw a3, 12(s0)
; RV32IZCMP-WITH-FP-NEXT: sw a2, 8(s0)
; RV32IZCMP-WITH-FP-NEXT: sw a1, 4(s0)
; RV32IZCMP-WITH-FP-NEXT: sw a0, 0(s0)
; RV32IZCMP-WITH-FP-NEXT: call callee@plt
; RV32IZCMP-WITH-FP-NEXT: lw ra, 12(sp) # 4-byte Folded Reload
; RV32IZCMP-WITH-FP-NEXT: lw s0, 8(sp) # 4-byte Folded Reload
; RV32IZCMP-WITH-FP-NEXT: addi sp, sp, 48
; RV32IZCMP-WITH-FP-NEXT: ret
;
; RV64I-LABEL: varargs:
; RV64I: # %bb.0:
; RV64I-NEXT: addi sp, sp, -80
; RV64I-NEXT: .cfi_def_cfa_offset 80
; RV64I-NEXT: sd ra, 8(sp) # 8-byte Folded Spill
; RV64I-NEXT: .cfi_offset ra, -72
; RV64I-NEXT: sd a7, 72(sp)
; RV64I-NEXT: sd a6, 64(sp)
; RV64I-NEXT: sd a5, 56(sp)
; RV64I-NEXT: sd a4, 48(sp)
; RV64I-NEXT: sd a3, 40(sp)
; RV64I-NEXT: sd a2, 32(sp)
; RV64I-NEXT: sd a1, 24(sp)
; RV64I-NEXT: sd a0, 16(sp)
; RV64I-NEXT: call callee@plt
; RV64I-NEXT: ld ra, 8(sp) # 8-byte Folded Reload
; RV64I-NEXT: addi sp, sp, 80
; RV64I-NEXT: ret
;
; RV64I-WITH-FP-LABEL: varargs:
; RV64I-WITH-FP: # %bb.0:
; RV64I-WITH-FP-NEXT: addi sp, sp, -80
; RV64I-WITH-FP-NEXT: .cfi_def_cfa_offset 80
; RV64I-WITH-FP-NEXT: sd ra, 8(sp) # 8-byte Folded Spill
; RV64I-WITH-FP-NEXT: sd s0, 0(sp) # 8-byte Folded Spill
; RV64I-WITH-FP-NEXT: .cfi_offset ra, -72
; RV64I-WITH-FP-NEXT: .cfi_offset s0, -80
; RV64I-WITH-FP-NEXT: addi s0, sp, 16
; RV64I-WITH-FP-NEXT: .cfi_def_cfa s0, 64
; RV64I-WITH-FP-NEXT: sd a7, 56(s0)
; RV64I-WITH-FP-NEXT: sd a6, 48(s0)
; RV64I-WITH-FP-NEXT: sd a5, 40(s0)
; RV64I-WITH-FP-NEXT: sd a4, 32(s0)
; RV64I-WITH-FP-NEXT: sd a3, 24(s0)
; RV64I-WITH-FP-NEXT: sd a2, 16(s0)
; RV64I-WITH-FP-NEXT: sd a1, 8(s0)
; RV64I-WITH-FP-NEXT: sd a0, 0(s0)
; RV64I-WITH-FP-NEXT: call callee@plt
; RV64I-WITH-FP-NEXT: ld ra, 8(sp) # 8-byte Folded Reload
; RV64I-WITH-FP-NEXT: ld s0, 0(sp) # 8-byte Folded Reload
; RV64I-WITH-FP-NEXT: addi sp, sp, 80
; RV64I-WITH-FP-NEXT: ret
;
; RV64IZCMP-LABEL: varargs:
; RV64IZCMP: # %bb.0:
; RV64IZCMP-NEXT: addi sp, sp, -80
; RV64IZCMP-NEXT: .cfi_def_cfa_offset 80
; RV64IZCMP-NEXT: sd ra, 8(sp) # 8-byte Folded Spill
; RV64IZCMP-NEXT: .cfi_offset ra, -72
; RV64IZCMP-NEXT: sd a7, 72(sp)
; RV64IZCMP-NEXT: sd a6, 64(sp)
; RV64IZCMP-NEXT: sd a5, 56(sp)
; RV64IZCMP-NEXT: sd a4, 48(sp)
; RV64IZCMP-NEXT: sd a3, 40(sp)
; RV64IZCMP-NEXT: sd a2, 32(sp)
; RV64IZCMP-NEXT: sd a1, 24(sp)
; RV64IZCMP-NEXT: sd a0, 16(sp)
; RV64IZCMP-NEXT: call callee@plt
; RV64IZCMP-NEXT: ld ra, 8(sp) # 8-byte Folded Reload
; RV64IZCMP-NEXT: addi sp, sp, 80
; RV64IZCMP-NEXT: ret
;
; RV64IZCMP-WITH-FP-LABEL: varargs:
; RV64IZCMP-WITH-FP: # %bb.0:
; RV64IZCMP-WITH-FP-NEXT: addi sp, sp, -80
; RV64IZCMP-WITH-FP-NEXT: .cfi_def_cfa_offset 80
; RV64IZCMP-WITH-FP-NEXT: sd ra, 8(sp) # 8-byte Folded Spill
; RV64IZCMP-WITH-FP-NEXT: sd s0, 0(sp) # 8-byte Folded Spill
; RV64IZCMP-WITH-FP-NEXT: .cfi_offset ra, -72
; RV64IZCMP-WITH-FP-NEXT: .cfi_offset s0, -80
; RV64IZCMP-WITH-FP-NEXT: addi s0, sp, 16
; RV64IZCMP-WITH-FP-NEXT: .cfi_def_cfa s0, 64
; RV64IZCMP-WITH-FP-NEXT: sd a7, 56(s0)
; RV64IZCMP-WITH-FP-NEXT: sd a6, 48(s0)
; RV64IZCMP-WITH-FP-NEXT: sd a5, 40(s0)
; RV64IZCMP-WITH-FP-NEXT: sd a4, 32(s0)
; RV64IZCMP-WITH-FP-NEXT: sd a3, 24(s0)
; RV64IZCMP-WITH-FP-NEXT: sd a2, 16(s0)
; RV64IZCMP-WITH-FP-NEXT: sd a1, 8(s0)
; RV64IZCMP-WITH-FP-NEXT: sd a0, 0(s0)
; RV64IZCMP-WITH-FP-NEXT: call callee@plt
; RV64IZCMP-WITH-FP-NEXT: ld ra, 8(sp) # 8-byte Folded Reload
; RV64IZCMP-WITH-FP-NEXT: ld s0, 0(sp) # 8-byte Folded Reload
; RV64IZCMP-WITH-FP-NEXT: addi sp, sp, 80
; RV64IZCMP-WITH-FP-NEXT: ret
call void @callee()
ret void
}