[llvm] [RISCV] Eliminate redundant materializations after register comparison (PR #227673)
via llvm-commits
llvm-commits at lists.llvm.org
Thu Oct 1 01:03:42 PDT 2026
https://github.com/tinfengyu updated https://github.com/llvm/llvm-project/pull/227673
>From a00bf0cd9539a43f9d31bc2ad50c3b178bde2312 Mon Sep 17 00:00:00 2001
From: tinfeng <1768309929 at qq.com>
Date: Thu, 1 Oct 2026 10:30:33 +0800
Subject: [PATCH 1/3] [RISCV] Add tests for redundant materializations after
register comparisons
---
.../RISCV/redundant-copy-elim-reg-imm.mir | 337 ++++++++++++++++++
1 file changed, 337 insertions(+)
create mode 100644 llvm/test/CodeGen/RISCV/redundant-copy-elim-reg-imm.mir
diff --git a/llvm/test/CodeGen/RISCV/redundant-copy-elim-reg-imm.mir b/llvm/test/CodeGen/RISCV/redundant-copy-elim-reg-imm.mir
new file mode 100644
index 0000000000000..16d8aca98fa25
--- /dev/null
+++ b/llvm/test/CodeGen/RISCV/redundant-copy-elim-reg-imm.mir
@@ -0,0 +1,337 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
+# RUN: llc -mtriple=riscv32 -mattr=+xqcili -run-pass=riscv-copyelim -verify-machineinstrs %s -o - | FileCheck %s
+
+--- |
+ define void @beq_reg_imm() { ret void }
+ define void @bne_reg_imm() { ret void }
+ define void @clobber_const() { ret void }
+ define void @clobber_target() { ret void }
+ define void @inequality_edge() { ret void }
+ define void @beq_x0_is_zero() { ret void }
+ define void @bne_x0_is_zero() { ret void }
+ define void @beq_reg_imm_swapped() { ret void }
+ define void @bne_reg_imm_swapped() { ret void }
+ declare void @callee()
+...
+---
+name: beq_reg_imm
+tracksRegLiveness: true
+body: |
+ ; CHECK-LABEL: name: beq_reg_imm
+ ; CHECK: bb.0:
+ ; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000)
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x11 = ADDI $x0, 7
+ ; CHECK-NEXT: BEQ $x11, killed $x10, %bb.1
+ ; CHECK-NEXT: PseudoBR %bb.2
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.1:
+ ; CHECK-NEXT: successors: %bb.2(0x80000000)
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x10 = ADDI $x0, 7
+ ; CHECK-NEXT: PseudoRET implicit $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.2:
+ ; CHECK-NEXT: PseudoRET
+ bb.0:
+ successors: %bb.1, %bb.2
+ liveins: $x10
+ $x11 = ADDI $x0, 7
+ BEQ $x11, killed $x10, %bb.1
+ PseudoBR %bb.2
+ bb.1:
+ successors: %bb.2
+ $x10 = ADDI $x0, 7
+ PseudoRET implicit $x10
+ bb.2:
+ PseudoRET
+...
+
+
+---
+name: bne_reg_imm
+tracksRegLiveness: true
+body: |
+ ; CHECK-LABEL: name: bne_reg_imm
+ ; CHECK: bb.0:
+ ; CHECK-NEXT: successors: %bb.2(0x40000000), %bb.1(0x40000000)
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x11 = QC_LI 9
+ ; CHECK-NEXT: BNE killed $x10, $x11, %bb.2
+ ; CHECK-NEXT: PseudoBR %bb.1
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.1:
+ ; CHECK-NEXT: $x10 = ADDI $x0, 9
+ ; CHECK-NEXT: PseudoRET implicit $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.2:
+ ; CHECK-NEXT: PseudoRET
+ bb.0:
+ successors: %bb.2, %bb.1
+ liveins: $x10
+ $x11 = QC_LI 9
+ BNE killed $x10, $x11, %bb.2
+ PseudoBR %bb.1
+ bb.1:
+ $x10 = ADDI $x0, 9
+ PseudoRET implicit $x10
+ bb.2:
+ PseudoRET
+...
+
+
+---
+name: clobber_const
+tracksRegLiveness: true
+body: |
+ ; CHECK-LABEL: name: clobber_const
+ ; CHECK: bb.0:
+ ; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000)
+ ; CHECK-NEXT: liveins: $x8
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x11 = ADDI $x0, 7
+ ; CHECK-NEXT: PseudoCALL target-flags(riscv-call) @callee, csr_ilp32_lp64, implicit-def dead $x1, implicit-def $x11
+ ; CHECK-NEXT: BEQ $x8, $x11, %bb.1
+ ; CHECK-NEXT: PseudoBR %bb.2
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.1:
+ ; CHECK-NEXT: $x8 = ADDI $x0, 7
+ ; CHECK-NEXT: PseudoRET implicit $x8
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.2:
+ ; CHECK-NEXT: liveins: $x8
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: PseudoRET implicit $x8
+ bb.0:
+ successors: %bb.1, %bb.2
+ liveins: $x8
+ $x11 = ADDI $x0, 7
+ PseudoCALL target-flags(riscv-call) @callee, csr_ilp32_lp64, implicit-def dead $x1, implicit-def $x11
+ BEQ $x8, $x11, %bb.1
+ PseudoBR %bb.2
+ bb.1:
+ $x8 = ADDI $x0, 7
+ PseudoRET implicit $x8
+ bb.2:
+ liveins: $x8
+ PseudoRET implicit $x8
+...
+
+
+---
+name: clobber_target
+tracksRegLiveness: true
+body: |
+ ; CHECK-LABEL: name: clobber_target
+ ; CHECK: bb.0:
+ ; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000)
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x11 = ADDI $x0, 7
+ ; CHECK-NEXT: BEQ $x10, $x11, %bb.1
+ ; CHECK-NEXT: PseudoBR %bb.2
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.1:
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x10 = ADDI $x10, 1
+ ; CHECK-NEXT: $x10 = ADDI $x0, 7
+ ; CHECK-NEXT: PseudoRET implicit $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.2:
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: PseudoRET implicit $x10
+ bb.0:
+ successors: %bb.1, %bb.2
+ liveins: $x10
+ $x11 = ADDI $x0, 7
+ BEQ $x10, $x11, %bb.1
+ PseudoBR %bb.2
+ bb.1:
+ liveins: $x10
+ $x10 = ADDI $x10, 1
+ $x10 = ADDI $x0, 7
+ PseudoRET implicit $x10
+ bb.2:
+ liveins: $x10
+ PseudoRET implicit $x10
+...
+
+
+---
+name: inequality_edge
+tracksRegLiveness: true
+body: |
+ ; CHECK-LABEL: name: inequality_edge
+ ; CHECK: bb.0:
+ ; CHECK-NEXT: successors: %bb.2(0x40000000), %bb.1(0x40000000)
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x11 = ADDI $x0, 7
+ ; CHECK-NEXT: BEQ $x10, $x11, %bb.2
+ ; CHECK-NEXT: PseudoBR %bb.1
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.1:
+ ; CHECK-NEXT: $x10 = ADDI $x0, 7
+ ; CHECK-NEXT: PseudoRET implicit $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.2:
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: PseudoRET implicit $x10
+ bb.0:
+ successors: %bb.2, %bb.1
+ liveins: $x10
+ $x11 = ADDI $x0, 7
+ BEQ $x10, $x11, %bb.2
+ PseudoBR %bb.1
+ bb.1:
+ $x10 = ADDI $x0, 7
+ PseudoRET implicit $x10
+ bb.2:
+ liveins: $x10
+ PseudoRET implicit $x10
+...
+
+
+---
+name: beq_x0_is_zero
+tracksRegLiveness: true
+body: |
+ ; CHECK-LABEL: name: beq_x0_is_zero
+ ; CHECK: bb.0:
+ ; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000)
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x0 = ADDI $x0, 7
+ ; CHECK-NEXT: BEQ $x0, $x10, %bb.1
+ ; CHECK-NEXT: PseudoBR %bb.2
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.1:
+ ; CHECK-NEXT: $x10 = ADDI $x0, 7
+ ; CHECK-NEXT: PseudoRET implicit $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.2:
+ ; CHECK-NEXT: PseudoRET
+ bb.0:
+ successors: %bb.1, %bb.2
+ liveins: $x10
+ $x0 = ADDI $x0, 7
+ BEQ $x0, $x10, %bb.1
+ PseudoBR %bb.2
+ bb.1:
+ $x10 = ADDI $x0, 7
+ PseudoRET implicit $x10
+ bb.2:
+ PseudoRET
+...
+
+# The formal ADDI definition cannot change x0's architectural zero value.
+
+---
+name: bne_x0_is_zero
+tracksRegLiveness: true
+body: |
+ ; CHECK-LABEL: name: bne_x0_is_zero
+ ; CHECK: bb.0:
+ ; CHECK-NEXT: successors: %bb.2(0x40000000), %bb.1(0x40000000)
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x0 = ADDI $x0, 9
+ ; CHECK-NEXT: BNE $x0, $x10, %bb.2
+ ; CHECK-NEXT: PseudoBR %bb.1
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.1:
+ ; CHECK-NEXT: $x10 = ADDI $x0, 9
+ ; CHECK-NEXT: PseudoRET implicit $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.2:
+ ; CHECK-NEXT: PseudoRET
+ bb.0:
+ successors: %bb.2, %bb.1
+ liveins: $x10
+ $x0 = ADDI $x0, 9
+ BNE $x0, $x10, %bb.2
+ PseudoBR %bb.1
+ bb.1:
+ $x10 = ADDI $x0, 9
+ PseudoRET implicit $x10
+ bb.2:
+ PseudoRET
+...
+
+
+---
+name: beq_reg_imm_swapped
+tracksRegLiveness: true
+body: |
+ ; CHECK-LABEL: name: beq_reg_imm_swapped
+ ; CHECK: bb.0:
+ ; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000)
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x11 = ADDI $x0, 7
+ ; CHECK-NEXT: BEQ killed $x10, $x11, %bb.1
+ ; CHECK-NEXT: PseudoBR %bb.2
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.1:
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x12 = ADDI killed $x10, 1
+ ; CHECK-NEXT: $x10 = ADDI $x0, 7
+ ; CHECK-NEXT: PseudoRET implicit $x10, implicit $x12
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.2:
+ ; CHECK-NEXT: PseudoRET
+ bb.0:
+ successors: %bb.1, %bb.2
+ liveins: $x10
+ $x11 = ADDI $x0, 7
+ BEQ killed $x10, $x11, %bb.1
+ PseudoBR %bb.2
+ bb.1:
+ liveins: $x10
+ $x12 = ADDI killed $x10, 1
+ $x10 = ADDI $x0, 7
+ PseudoRET implicit $x10, implicit $x12
+ bb.2:
+ PseudoRET
+...
+
+# The compared value is the first branch operand. Its kill in the successor
+# must be cleared when the later materialization is removed.
+
+---
+name: bne_reg_imm_swapped
+tracksRegLiveness: true
+body: |
+ ; CHECK-LABEL: name: bne_reg_imm_swapped
+ ; CHECK: bb.0:
+ ; CHECK-NEXT: successors: %bb.2(0x40000000), %bb.1(0x40000000)
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: $x11 = ADDI $x0, 9
+ ; CHECK-NEXT: BNE $x11, killed $x10, %bb.2
+ ; CHECK-NEXT: PseudoBR %bb.1
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.1:
+ ; CHECK-NEXT: $x10 = ADDI $x0, 9
+ ; CHECK-NEXT: PseudoRET implicit $x10
+ ; CHECK-NEXT: {{ $}}
+ ; CHECK-NEXT: bb.2:
+ ; CHECK-NEXT: PseudoRET
+ bb.0:
+ successors: %bb.2, %bb.1
+ liveins: $x10
+ $x11 = ADDI $x0, 9
+ BNE $x11, killed $x10, %bb.2
+ PseudoBR %bb.1
+ bb.1:
+ $x10 = ADDI $x0, 9
+ PseudoRET implicit $x10
+ bb.2:
+ PseudoRET
+...
>From 8069c49727011931c0449c0d278006bd267ca2a0 Mon Sep 17 00:00:00 2001
From: tinfeng <1768309929 at qq.com>
Date: Thu, 1 Oct 2026 12:08:31 +0800
Subject: [PATCH 2/3] [RISCV] Eliminate redundant materializations after
register comparisons
---
.../RISCV/RISCVRedundantCopyElimination.cpp | 68 +++++++++++++++++--
.../RISCV/redundant-copy-elim-reg-imm.mir | 19 +++---
.../test/CodeGen/RISCV/redundant-copy-elim.ll | 9 +--
.../RISCV/xandesperf-redundant-copy-elim.ll | 9 +--
.../RISCV/xqcibi-redundant-copy-elim.ll | 16 ++---
5 files changed, 84 insertions(+), 37 deletions(-)
diff --git a/llvm/lib/Target/RISCV/RISCVRedundantCopyElimination.cpp b/llvm/lib/Target/RISCV/RISCVRedundantCopyElimination.cpp
index 2e0e6ab2408d7..327c2104b7958 100644
--- a/llvm/lib/Target/RISCV/RISCVRedundantCopyElimination.cpp
+++ b/llvm/lib/Target/RISCV/RISCVRedundantCopyElimination.cpp
@@ -20,8 +20,8 @@
// This pass should be run after register allocation and is based on the
// earliest versions of AArch64RedundantCopyElimination.
//
-// FIXME: Support compare with non-zero immediates where the immediate is stored
-// in a register.
+// The pass also handles register-register branches when one operand is
+// materialized as a non-zero immediate in the predecessor block.
//
//===----------------------------------------------------------------------===//
@@ -32,6 +32,7 @@
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterClassInfo.h"
#include "llvm/Support/Debug.h"
+#include <optional>
using namespace llvm;
@@ -108,6 +109,32 @@ guaranteesRegEqualsImmInBlock(MachineBasicBlock &MBB,
return false;
}
+static std::optional<int64_t>
+getRegImmediateBeforeTerminator(MachineBasicBlock &MBB, Register Reg,
+ const TargetRegisterInfo *TRI) {
+ // A write to X0 is discarded, so it cannot establish a nonzero value.
+ if (Reg == RISCV::X0)
+ return std::nullopt;
+
+ for (auto I = MBB.getFirstTerminator(); I != MBB.begin();) {
+ MachineInstr &MI = *--I;
+ if (!MI.modifiesRegister(Reg, TRI))
+ continue;
+ // The last modification must define Reg itself to a known immediate.
+ if (MI.getOpcode() == RISCV::ADDI && MI.getOperand(0).isReg() &&
+ MI.getOperand(0).getReg() == Reg &&
+ MI.getOperand(1).isReg() && MI.getOperand(1).getReg() == RISCV::X0 &&
+ MI.getOperand(2).isImm())
+ return MI.getOperand(2).getImm();
+ if (MI.getOpcode() == RISCV::QC_LI && MI.getOperand(0).isReg() &&
+ MI.getOperand(0).getReg() == Reg &&
+ MI.getOperand(1).isImm())
+ return MI.getOperand(1).getImm();
+ return std::nullopt;
+ }
+ return std::nullopt;
+}
+
bool RISCVRedundantCopyElimination::optimizeBlock(MachineBasicBlock &MBB) {
// Check if the current basic block has a single predecessor.
if (MBB.pred_size() != 1)
@@ -131,8 +158,35 @@ bool RISCVRedundantCopyElimination::optimizeBlock(MachineBasicBlock &MBB) {
return false;
bool IsZeroCopy = guaranteesZeroRegInBlock(MBB, Cond, TBB);
+ bool IsImmCopy =
+ !IsZeroCopy && guaranteesRegEqualsImmInBlock(MBB, Cond, TBB);
+ int64_t CompareImm = IsImmCopy ? Cond[2].getImm() : 0;
+ if (!IsZeroCopy && !IsImmCopy && Cond.size() == 3 &&
+ (Cond[0].getImm() == RISCV::BEQ || Cond[0].getImm() == RISCV::BNE) &&
+ Cond[2].isReg()) {
+ // One branch operand may have been materialized with ADDI or QC_LI.
+ // The other operand is known to have the same value on the equality edge,
+ // irrespective of the operand order.
+ std::optional<int64_t> Imm =
+ getRegImmediateBeforeTerminator(*PredMBB, Cond[2].getReg(), TRI);
+ if (Imm && *Imm != 0) {
+ TargetReg = Cond[1].getReg();
+ CompareImm = *Imm;
+ IsImmCopy = true;
+ } else {
+ Imm = getRegImmediateBeforeTerminator(*PredMBB, Cond[1].getReg(), TRI);
+ if (Imm && *Imm != 0) {
+ TargetReg = Cond[2].getReg();
+ CompareImm = *Imm;
+ IsImmCopy = true;
+ }
+ }
+ // For BEQ, equality is guaranteed on the taken edge. For BNE, it is
+ // guaranteed on the fallthrough edge.
+ IsImmCopy &= (Cond[0].getImm() == RISCV::BEQ) == (TBB == &MBB);
+ }
- if (!IsZeroCopy && !guaranteesRegEqualsImmInBlock(MBB, Cond, TBB))
+ if (!IsZeroCopy && !IsImmCopy)
return false;
bool Changed = false;
@@ -161,14 +215,14 @@ bool RISCVRedundantCopyElimination::optimizeBlock(MachineBasicBlock &MBB) {
Register SrcReg = MI->getOperand(1).getReg();
int64_t Imm = MI->getOperand(2).getImm();
if (SrcReg == RISCV::X0 && !MRI->isReserved(DefReg) &&
- TargetReg == DefReg && Imm == Cond[2].getImm())
+ TargetReg == DefReg && Imm == CompareImm)
RemoveMI = true;
} else if (MI->getOpcode() == RISCV::QC_LI && MI->getOperand(0).isReg() &&
MI->getOperand(1).isImm()) {
Register DefReg = MI->getOperand(0).getReg();
int64_t Imm = MI->getOperand(1).getImm();
if (!MRI->isReserved(DefReg) && TargetReg == DefReg &&
- Imm == Cond[2].getImm())
+ Imm == CompareImm)
RemoveMI = true;
}
}
@@ -203,7 +257,9 @@ bool RISCVRedundantCopyElimination::optimizeBlock(MachineBasicBlock &MBB) {
CondBr->getOpcode() == RISCV::NDS_BEQC ||
CondBr->getOpcode() == RISCV::NDS_BNEC) &&
"Unexpected opcode");
- assert(CondBr->getOperand(0).getReg() == TargetReg && "Unexpected register");
+ assert((CondBr->getOperand(0).getReg() == TargetReg ||
+ CondBr->getOperand(1).getReg() == TargetReg) &&
+ "Unexpected register");
// Otherwise, we have to fixup the use-def chain, starting with the
// BEQ(I)/BNE(I). Conservatively mark as much as we can live.
diff --git a/llvm/test/CodeGen/RISCV/redundant-copy-elim-reg-imm.mir b/llvm/test/CodeGen/RISCV/redundant-copy-elim-reg-imm.mir
index 16d8aca98fa25..162f118b1b583 100644
--- a/llvm/test/CodeGen/RISCV/redundant-copy-elim-reg-imm.mir
+++ b/llvm/test/CodeGen/RISCV/redundant-copy-elim-reg-imm.mir
@@ -23,13 +23,13 @@ body: |
; CHECK-NEXT: liveins: $x10
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x11 = ADDI $x0, 7
- ; CHECK-NEXT: BEQ $x11, killed $x10, %bb.1
+ ; CHECK-NEXT: BEQ $x11, $x10, %bb.1
; CHECK-NEXT: PseudoBR %bb.2
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: successors: %bb.2(0x80000000)
+ ; CHECK-NEXT: liveins: $x10
; CHECK-NEXT: {{ $}}
- ; CHECK-NEXT: $x10 = ADDI $x0, 7
; CHECK-NEXT: PseudoRET implicit $x10
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.2:
@@ -59,11 +59,12 @@ body: |
; CHECK-NEXT: liveins: $x10
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x11 = QC_LI 9
- ; CHECK-NEXT: BNE killed $x10, $x11, %bb.2
+ ; CHECK-NEXT: BNE $x10, $x11, %bb.2
; CHECK-NEXT: PseudoBR %bb.1
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
- ; CHECK-NEXT: $x10 = ADDI $x0, 9
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
; CHECK-NEXT: PseudoRET implicit $x10
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.2:
@@ -274,14 +275,13 @@ body: |
; CHECK-NEXT: liveins: $x10
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x11 = ADDI $x0, 7
- ; CHECK-NEXT: BEQ killed $x10, $x11, %bb.1
+ ; CHECK-NEXT: BEQ $x10, $x11, %bb.1
; CHECK-NEXT: PseudoBR %bb.2
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: liveins: $x10
; CHECK-NEXT: {{ $}}
- ; CHECK-NEXT: $x12 = ADDI killed $x10, 1
- ; CHECK-NEXT: $x10 = ADDI $x0, 7
+ ; CHECK-NEXT: $x12 = ADDI $x10, 1
; CHECK-NEXT: PseudoRET implicit $x10, implicit $x12
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.2:
@@ -314,11 +314,12 @@ body: |
; CHECK-NEXT: liveins: $x10
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x11 = ADDI $x0, 9
- ; CHECK-NEXT: BNE $x11, killed $x10, %bb.2
+ ; CHECK-NEXT: BNE $x11, $x10, %bb.2
; CHECK-NEXT: PseudoBR %bb.1
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
- ; CHECK-NEXT: $x10 = ADDI $x0, 9
+ ; CHECK-NEXT: liveins: $x10
+ ; CHECK-NEXT: {{ $}}
; CHECK-NEXT: PseudoRET implicit $x10
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.2:
diff --git a/llvm/test/CodeGen/RISCV/redundant-copy-elim.ll b/llvm/test/CodeGen/RISCV/redundant-copy-elim.ll
index a93514dfaedc6..cc72d46c0de85 100644
--- a/llvm/test/CodeGen/RISCV/redundant-copy-elim.ll
+++ b/llvm/test/CodeGen/RISCV/redundant-copy-elim.ll
@@ -8,12 +8,10 @@ define i32 @test_beqi(i32 %a) nounwind {
; RV32I-LABEL: test_beqi:
; RV32I: # %bb.0: # %entry
; RV32I-NEXT: li a1, 7
-; RV32I-NEXT: bne a0, a1, .LBB0_2
-; RV32I-NEXT: # %bb.1: # %if.end
-; RV32I-NEXT: li a0, 7
-; RV32I-NEXT: ret
-; RV32I-NEXT: .LBB0_2: # %if.then
+; RV32I-NEXT: beq a0, a1, .LBB0_2
+; RV32I-NEXT: # %bb.1: # %if.then
; RV32I-NEXT: li a0, 1
+; RV32I-NEXT: .LBB0_2: # %if.end
; RV32I-NEXT: ret
;
; RV32IZIBI-LABEL: test_beqi:
@@ -41,7 +39,6 @@ define i32 @test_bnei(i32 %a) nounwind {
; RV32I-NEXT: li a0, 1
; RV32I-NEXT: ret
; RV32I-NEXT: .LBB1_2: # %if.then
-; RV32I-NEXT: li a0, 7
; RV32I-NEXT: ret
;
; RV32IZIBI-LABEL: test_bnei:
diff --git a/llvm/test/CodeGen/RISCV/xandesperf-redundant-copy-elim.ll b/llvm/test/CodeGen/RISCV/xandesperf-redundant-copy-elim.ll
index d01eb2082a6fc..12497baa67556 100644
--- a/llvm/test/CodeGen/RISCV/xandesperf-redundant-copy-elim.ll
+++ b/llvm/test/CodeGen/RISCV/xandesperf-redundant-copy-elim.ll
@@ -8,12 +8,10 @@ define i32 @test_beqc(i32 %a) nounwind {
; RV32I-LABEL: test_beqc:
; RV32I: # %bb.0: # %entry
; RV32I-NEXT: li a1, 7
-; RV32I-NEXT: bne a0, a1, .LBB0_2
-; RV32I-NEXT: # %bb.1: # %if.end
-; RV32I-NEXT: li a0, 7
-; RV32I-NEXT: ret
-; RV32I-NEXT: .LBB0_2: # %if.then
+; RV32I-NEXT: beq a0, a1, .LBB0_2
+; RV32I-NEXT: # %bb.1: # %if.then
; RV32I-NEXT: li a0, 1
+; RV32I-NEXT: .LBB0_2: # %if.end
; RV32I-NEXT: ret
;
; RV32IXANDESPERF-LABEL: test_beqc:
@@ -41,7 +39,6 @@ define i32 @test_bnec(i32 %a) nounwind {
; RV32I-NEXT: li a0, 1
; RV32I-NEXT: ret
; RV32I-NEXT: .LBB1_2: # %if.then
-; RV32I-NEXT: li a0, 7
; RV32I-NEXT: ret
;
; RV32IXANDESPERF-LABEL: test_bnec:
diff --git a/llvm/test/CodeGen/RISCV/xqcibi-redundant-copy-elim.ll b/llvm/test/CodeGen/RISCV/xqcibi-redundant-copy-elim.ll
index df5c6a21b0868..8bd370c48947f 100644
--- a/llvm/test/CodeGen/RISCV/xqcibi-redundant-copy-elim.ll
+++ b/llvm/test/CodeGen/RISCV/xqcibi-redundant-copy-elim.ll
@@ -10,12 +10,10 @@ define dso_local i32 @test_beqi(i32 %a) nounwind {
; RV32I-LABEL: test_beqi:
; RV32I: # %bb.0: # %entry
; RV32I-NEXT: li a1, 7
-; RV32I-NEXT: bne a0, a1, .LBB0_2
-; RV32I-NEXT: # %bb.1: # %if.end
-; RV32I-NEXT: li a0, 7
-; RV32I-NEXT: ret
-; RV32I-NEXT: .LBB0_2: # %if.then
+; RV32I-NEXT: beq a0, a1, .LBB0_2
+; RV32I-NEXT: # %bb.1: # %if.then
; RV32I-NEXT: li a0, 1
+; RV32I-NEXT: .LBB0_2: # %if.end
; RV32I-NEXT: ret
;
; RV32IXQCIBI-LABEL: test_beqi:
@@ -54,12 +52,10 @@ define dso_local i32 @test_e_beqi(i32 %a) nounwind {
; RV32I-LABEL: test_e_beqi:
; RV32I: # %bb.0: # %entry
; RV32I-NEXT: li a1, 40
-; RV32I-NEXT: bne a0, a1, .LBB1_2
-; RV32I-NEXT: # %bb.1: # %if.end
-; RV32I-NEXT: li a0, 40
-; RV32I-NEXT: ret
-; RV32I-NEXT: .LBB1_2: # %if.then
+; RV32I-NEXT: beq a0, a1, .LBB1_2
+; RV32I-NEXT: # %bb.1: # %if.then
; RV32I-NEXT: li a0, 1
+; RV32I-NEXT: .LBB1_2: # %if.end
; RV32I-NEXT: ret
;
; RV32IXQCIBI-LABEL: test_e_beqi:
>From d0bf60559666614fe219f7d22c2f9b43a29c5f29 Mon Sep 17 00:00:00 2001
From: tinfeng <1768309929 at qq.com>
Date: Thu, 1 Oct 2026 16:02:47 +0800
Subject: [PATCH 3/3] [RISCV] Fix formatting
---
.../Target/RISCV/RISCVRedundantCopyElimination.cpp | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/llvm/lib/Target/RISCV/RISCVRedundantCopyElimination.cpp b/llvm/lib/Target/RISCV/RISCVRedundantCopyElimination.cpp
index 327c2104b7958..ccf9fc2b040f6 100644
--- a/llvm/lib/Target/RISCV/RISCVRedundantCopyElimination.cpp
+++ b/llvm/lib/Target/RISCV/RISCVRedundantCopyElimination.cpp
@@ -122,13 +122,11 @@ getRegImmediateBeforeTerminator(MachineBasicBlock &MBB, Register Reg,
continue;
// The last modification must define Reg itself to a known immediate.
if (MI.getOpcode() == RISCV::ADDI && MI.getOperand(0).isReg() &&
- MI.getOperand(0).getReg() == Reg &&
- MI.getOperand(1).isReg() && MI.getOperand(1).getReg() == RISCV::X0 &&
- MI.getOperand(2).isImm())
+ MI.getOperand(0).getReg() == Reg && MI.getOperand(1).isReg() &&
+ MI.getOperand(1).getReg() == RISCV::X0 && MI.getOperand(2).isImm())
return MI.getOperand(2).getImm();
if (MI.getOpcode() == RISCV::QC_LI && MI.getOperand(0).isReg() &&
- MI.getOperand(0).getReg() == Reg &&
- MI.getOperand(1).isImm())
+ MI.getOperand(0).getReg() == Reg && MI.getOperand(1).isImm())
return MI.getOperand(1).getImm();
return std::nullopt;
}
@@ -158,8 +156,7 @@ bool RISCVRedundantCopyElimination::optimizeBlock(MachineBasicBlock &MBB) {
return false;
bool IsZeroCopy = guaranteesZeroRegInBlock(MBB, Cond, TBB);
- bool IsImmCopy =
- !IsZeroCopy && guaranteesRegEqualsImmInBlock(MBB, Cond, TBB);
+ bool IsImmCopy = !IsZeroCopy && guaranteesRegEqualsImmInBlock(MBB, Cond, TBB);
int64_t CompareImm = IsImmCopy ? Cond[2].getImm() : 0;
if (!IsZeroCopy && !IsImmCopy && Cond.size() == 3 &&
(Cond[0].getImm() == RISCV::BEQ || Cond[0].getImm() == RISCV::BNE) &&
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