diff --git a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp index 542be1c20efc0..5698fc2d6f9f5 100644 --- a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp +++ b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp @@ -22190,6 +22190,7 @@ static MachineBasicBlock *emitSelectPseudo(MachineInstr &MI, // - They are debug instructions. Otherwise, // - They do not have side-effects, do not access memory and their inputs do // not depend on the results of the select pseudo-instructions. + // - They don't adjust stack. // The TrueV/FalseV operands of the selects cannot depend on the result of // previous selects in the sequence. // These conditions could be further relaxed. See the X86 target for a @@ -22218,6 +22219,8 @@ static MachineBasicBlock *emitSelectPseudo(MachineInstr &MI, SelectDests.insert(MI.getOperand(0).getReg()); MachineInstr *LastSelectPseudo = &MI; + const RISCVInstrInfo &TII = *Subtarget.getInstrInfo(); + for (auto E = BB->end(), SequenceMBBI = MachineBasicBlock::iterator(MI); SequenceMBBI != E; ++SequenceMBBI) { if (SequenceMBBI->isDebugInstr()) @@ -22237,7 +22240,9 @@ static MachineBasicBlock *emitSelectPseudo(MachineInstr &MI, } if (SequenceMBBI->hasUnmodeledSideEffects() || SequenceMBBI->mayLoadOrStore() || - SequenceMBBI->usesCustomInsertionHook()) + SequenceMBBI->usesCustomInsertionHook() || + TII.isFrameInstr(*SequenceMBBI) || + SequenceMBBI->isStackAligningInlineAsm()) break; if (llvm::any_of(SequenceMBBI->operands(), [&](MachineOperand &MO) { return MO.isReg() && MO.isUse() && SelectDests.count(MO.getReg()); @@ -22245,7 +22250,6 @@ static MachineBasicBlock *emitSelectPseudo(MachineInstr &MI, break; } - const RISCVInstrInfo &TII = *Subtarget.getInstrInfo(); const BasicBlock *LLVM_BB = BB->getBasicBlock(); DebugLoc DL = MI.getDebugLoc(); MachineFunction::iterator I = ++BB->getIterator(); diff --git a/llvm/test/CodeGen/RISCV/select-pseudo-merge-with-stack-adj.ll b/llvm/test/CodeGen/RISCV/select-pseudo-merge-with-stack-adj.ll new file mode 100644 index 0000000000000..f0941120fc806 --- /dev/null +++ b/llvm/test/CodeGen/RISCV/select-pseudo-merge-with-stack-adj.ll @@ -0,0 +1,64 @@ +; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6 +; RUN: llc %s -mtriple riscv32 -verify-machineinstrs -o - | FileCheck %s + +define i32 @test(i1 %arg_1, i32 %arg_2) { +; CHECK-LABEL: test: +; CHECK: # %bb.0: # %entry +; CHECK-NEXT: addi sp, sp, -16 +; CHECK-NEXT: .cfi_def_cfa_offset 16 +; CHECK-NEXT: sw ra, 12(sp) # 4-byte Folded Spill +; CHECK-NEXT: sw s0, 8(sp) # 4-byte Folded Spill +; CHECK-NEXT: sw s1, 4(sp) # 4-byte Folded Spill +; CHECK-NEXT: .cfi_offset ra, -4 +; CHECK-NEXT: .cfi_offset s0, -8 +; CHECK-NEXT: .cfi_offset s1, -12 +; CHECK-NEXT: andi s1, a0, 1 +; CHECK-NEXT: mv a0, a1 +; CHECK-NEXT: mv s0, a1 +; CHECK-NEXT: bnez s1, .LBB0_2 +; CHECK-NEXT: # %bb.1: # %entry +; CHECK-NEXT: li s0, 1 +; CHECK-NEXT: .LBB0_2: # %entry +; CHECK-NEXT: li a1, 7 +; CHECK-NEXT: call __udivsi3 +; CHECK-NEXT: bnez s1, .LBB0_4 +; CHECK-NEXT: # %bb.3: # %entry +; CHECK-NEXT: li a0, 3 +; CHECK-NEXT: .LBB0_4: # %entry +; CHECK-NEXT: bnez s1, .LBB0_6 +; CHECK-NEXT: # %bb.5: # %entry +; CHECK-NEXT: mv s0, a0 +; CHECK-NEXT: .LBB0_6: # %entry +; CHECK-NEXT: li a0, 3 +; CHECK-NEXT: .LBB0_7: # %body +; CHECK-NEXT: # =>This Inner Loop Header: Depth=1 +; CHECK-NEXT: addi s0, s0, 4 +; CHECK-NEXT: bltu a0, s0, .LBB0_7 +; CHECK-NEXT: # %bb.8: # %exit +; CHECK-NEXT: mv a0, s0 +; CHECK-NEXT: lw ra, 12(sp) # 4-byte Folded Reload +; CHECK-NEXT: lw s0, 8(sp) # 4-byte Folded Reload +; CHECK-NEXT: lw s1, 4(sp) # 4-byte Folded Reload +; CHECK-NEXT: .cfi_restore ra +; CHECK-NEXT: .cfi_restore s0 +; CHECK-NEXT: .cfi_restore s1 +; CHECK-NEXT: addi sp, sp, 16 +; CHECK-NEXT: .cfi_def_cfa_offset 0 +; CHECK-NEXT: ret +entry: + %sel_1 = select i1 %arg_1, i32 %arg_2, i32 1 + %div = udiv i32 %arg_2, 7 + %cond_1 = icmp ugt i32 %div, %sel_1 + %sel_2 = select i1 %arg_1, i32 %div, i32 3 + %sel = select i1 %arg_1, i32 %sel_1, i32 %sel_2 + br label %body + +body: + %res = phi i32 [ %sel, %entry ], [ %add_loop, %body ] + %add_loop = add i32 4, %res + %cond_2 = icmp ugt i32 %add_loop, 3 + br i1 %cond_2, label %body, label %exit + +exit: + ret i32 %add_loop +}