Revert "[ARM][Thumb2] Mark BTI-clearing instructions as scheduling region boundaries"

[vhscampos]

Reverts #79173

The testcase fails in non-asserts builds.

[llvmbot]

@llvm/pr-subscribers-backend-arm

Author: Victor Campos (vhscampos)

Changes

Reverts llvm/llvm-project#79173

The testcase fails in non-asserts builds.

---

Full diff: https://github.com/llvm/llvm-project/pull/87699.diff

3 Files Affected:

• (modified) llvm/lib/Target/ARM/Thumb2InstrInfo.cpp (-19)
• (modified) llvm/lib/Target/ARM/Thumb2InstrInfo.h (-4)
• (removed) llvm/test/CodeGen/ARM/misched-branch-targets.mir (-166)

diff --git a/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp b/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp
index fc2834cb0b45c7..083f25f49dec45 100644
--- a/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp
+++ b/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp
@@ -286,25 +286,6 @@ MachineInstr *Thumb2InstrInfo::commuteInstructionImpl(MachineInstr &MI,
   return ARMBaseInstrInfo::commuteInstructionImpl(MI, NewMI, OpIdx1, OpIdx2);
 }
 
-bool Thumb2InstrInfo::isSchedulingBoundary(const MachineInstr &MI,
-                                           const MachineBasicBlock *MBB,
-                                           const MachineFunction &MF) const {
-  // BTI clearing instructions shall not take part in scheduling regions as
-  // they must stay in their intended place. Although PAC isn't BTI clearing,
-  // it can be transformed into PACBTI after the pre-RA Machine Scheduling
-  // has taken place, so its movement must also be restricted.
-  switch (MI.getOpcode()) {
-  case ARM::t2BTI:
-  case ARM::t2PAC:
-  case ARM::t2PACBTI:
-  case ARM::t2SG:
-    return true;
-  default:
-    break;
-  }
-  return ARMBaseInstrInfo::isSchedulingBoundary(MI, MBB, MF);
-}
-
 void llvm::emitT2RegPlusImmediate(MachineBasicBlock &MBB,
                                   MachineBasicBlock::iterator &MBBI,
                                   const DebugLoc &dl, Register DestReg,
diff --git a/llvm/lib/Target/ARM/Thumb2InstrInfo.h b/llvm/lib/Target/ARM/Thumb2InstrInfo.h
index 8915da8c5bf3c8..4bb412f09dcbeb 100644
--- a/llvm/lib/Target/ARM/Thumb2InstrInfo.h
+++ b/llvm/lib/Target/ARM/Thumb2InstrInfo.h
@@ -68,10 +68,6 @@ class Thumb2InstrInfo : public ARMBaseInstrInfo {
                                        unsigned OpIdx1,
                                        unsigned OpIdx2) const override;
 
-  bool isSchedulingBoundary(const MachineInstr &MI,
-                            const MachineBasicBlock *MBB,
-                            const MachineFunction &MF) const override;
-
 private:
   void expandLoadStackGuard(MachineBasicBlock::iterator MI) const override;
 };
diff --git a/llvm/test/CodeGen/ARM/misched-branch-targets.mir b/llvm/test/CodeGen/ARM/misched-branch-targets.mir
deleted file mode 100644
index b071fbd4538a6d..00000000000000
--- a/llvm/test/CodeGen/ARM/misched-branch-targets.mir
+++ /dev/null
@@ -1,166 +0,0 @@
-# RUN: llc -o - -run-pass=machine-scheduler -misched=shuffle %s | FileCheck %s
-# RUN: llc -o - -run-pass=postmisched %s | FileCheck %s
-
---- |
-  target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
-  target triple = "thumbv8.1m.main-arm-none-eabi"
-
-  define i32 @foo_bti() #0 {
-  entry:
-    ret i32 0
-  }
-
-  define i32 @foo_pac() #0 {
-  entry:
-    ret i32 0
-  }
-
-  define i32 @foo_pacbti() #0 {
-  entry:
-    ret i32 0
-  }
-
-  define i32 @foo_setjmp() #0 {
-  entry:
-    ret i32 0
-  if.then:
-    ret i32 0
-  }
-
-  define i32 @foo_sg() #0 {
-  entry:
-    ret i32 0
-  }
-
-  declare i32 @setjmp(ptr noundef) #1
-  declare void @longjmp(ptr noundef, i32 noundef) #2
-
-  attributes #0 = { "frame-pointer"="all" "target-cpu"="cortex-m55" "target-features"="+armv8.1-m.main" }
-  attributes #1 = { nounwind returns_twice "frame-pointer"="all" "target-cpu"="cortex-m55" "target-features"="+armv8.1-m.main" }
-  attributes #2 = { noreturn nounwind "frame-pointer"="all" "target-cpu"="cortex-m55" "target-features"="+armv8.1-m.main" }
-
-...
----
-name:            foo_bti
-tracksRegLiveness: true
-body:             |
-  bb.0.entry:
-    liveins: $r0
-
-    t2BTI
-    renamable $r0, dead $cpsr = nsw tADDi8 killed renamable $r0, 1, 14 /* CC::al */, $noreg
-    tBX_RET 14 /* CC::al */, $noreg, implicit killed $r0
-
-...
-
-# CHECK-LABEL: name:            foo_bti
-# CHECK:       body:
-# CHECK-NEXT:   bb.0.entry:
-# CHECK-NEXT:     liveins: $r0
-# CHECK-NEXT:     {{^ +$}}
-# CHECK-NEXT:     t2BTI
-
----
-name:            foo_pac
-tracksRegLiveness: true
-body:             |
-  bb.0.entry:
-    liveins: $r0, $lr, $r12
-
-    frame-setup t2PAC implicit-def $r12, implicit $lr, implicit $sp
-    renamable $r2 = nsw t2ADDri $r0, 3, 14 /* CC::al */, $noreg, $noreg
-    $sp = frame-setup t2STMDB_UPD $sp, 14 /* CC::al */, $noreg, killed $r7, killed $lr
-    $r7 = frame-setup tMOVr killed $sp, 14 /* CC::al */, $noreg
-    early-clobber $sp = frame-setup t2STR_PRE killed $r12, $sp, -4, 14 /* CC::al */, $noreg
-    $r12, $sp = frame-destroy t2LDR_POST $sp, 4, 14 /* CC::al */, $noreg
-    $sp = frame-destroy t2LDMIA_UPD $sp, 14 /* CC::al */, $noreg, def $r7, def $lr
-    t2AUT implicit $r12, implicit $lr, implicit $sp
-    tBX_RET 14 /* CC::al */, $noreg, implicit $r0
-
-...
-
-# CHECK-LABEL: name:            foo_pac
-# CHECK:       body:
-# CHECK-NEXT:    bb.0.entry:
-# CHECK-NEXT:      liveins: $r0, $lr, $r12
-# CHECK-NEXT:      {{^ +$}}
-# CHECK-NEXT:      frame-setup t2PAC implicit-def $r12, implicit $lr, implicit $sp
-
----
-name:            foo_pacbti
-tracksRegLiveness: true
-body:             |
-  bb.0.entry:
-    liveins: $r0, $lr, $r12
-
-    frame-setup t2PACBTI implicit-def $r12, implicit $lr, implicit $sp
-    renamable $r2 = nsw t2ADDri $r0, 3, 14 /* CC::al */, $noreg, $noreg
-    $sp = frame-setup t2STMDB_UPD $sp, 14 /* CC::al */, $noreg, killed $r7, killed $lr
-    $r7 = frame-setup tMOVr killed $sp, 14 /* CC::al */, $noreg
-    early-clobber $sp = frame-setup t2STR_PRE killed $r12, $sp, -4, 14 /* CC::al */, $noreg
-    $r12, $sp = frame-destroy t2LDR_POST $sp, 4, 14 /* CC::al */, $noreg
-    $sp = frame-destroy t2LDMIA_UPD $sp, 14 /* CC::al */, $noreg, def $r7, def $lr
-    t2AUT implicit $r12, implicit $lr, implicit $sp
-    tBX_RET 14 /* CC::al */, $noreg, implicit $r0
-
-...
-
-# CHECK-LABEL: name:            foo_pacbti
-# CHECK:       body:
-# CHECK-NEXT:    bb.0.entry:
-# CHECK-NEXT:      liveins: $r0, $lr, $r12
-# CHECK-NEXT:      {{^ +$}}
-# CHECK-NEXT:      frame-setup t2PACBTI implicit-def $r12, implicit $lr, implicit $sp
-
----
-name:            foo_setjmp
-tracksRegLiveness: true
-body:             |
-  bb.0.entry:
-    successors: %bb.1
-    liveins: $lr
-
-    frame-setup tPUSH 14 /* CC::al */, $noreg, $r7, killed $lr, implicit-def $sp, implicit $sp
-    $r7 = frame-setup tMOVr $sp, 14 /* CC::al */, $noreg
-    $sp = frame-setup tSUBspi $sp, 40, 14 /* CC::al */, $noreg
-    renamable $r0 = tMOVr $sp, 14 /* CC::al */, $noreg
-    tBL 14 /* CC::al */, $noreg, @setjmp, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $r0, implicit-def $sp, implicit-def $r0
-    t2BTI
-    renamable $r2 = nsw t2ADDri $r0, 3, 14 /* CC::al */, $noreg, $noreg
-    tCMPi8 killed renamable $r0, 0, 14 /* CC::al */, $noreg, implicit-def $cpsr
-    t2IT 0, 2, implicit-def $itstate
-    renamable $r0 = tMOVi8 $noreg, 0, 0 /* CC::eq */, $cpsr, implicit $itstate
-    $sp = frame-destroy tADDspi $sp, 40, 0 /* CC::eq */, $cpsr, implicit $itstate
-    frame-destroy tPOP_RET 0 /* CC::eq */, killed $cpsr, def $r7, def $pc, implicit killed $r0, implicit $sp, implicit killed $itstate
-
-  bb.1.if.then:
-    renamable $r0 = tMOVr $sp, 14 /* CC::al */, $noreg
-    renamable $r1, dead $cpsr = tMOVi8 1, 14 /* CC::al */, $noreg
-    tBL 14 /* CC::al */, $noreg, @longjmp, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $r0, implicit killed $r1, implicit-def $sp
-
-...
-
-# CHECK-LABEL: name:            foo_setjmp
-# CHECK:       body:
-# CHECK:         tBL 14 /* CC::al */, $noreg, @setjmp, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $r0, implicit-def $sp, implicit-def $r0
-# CHECK-NEXT:    t2BTI
-
----
-name:            foo_sg
-tracksRegLiveness: true
-body:             |
-  bb.0.entry:
-    liveins: $r0
-
-    t2SG 14 /* CC::al */, $noreg
-    renamable $r0, dead $cpsr = nsw tADDi8 killed renamable $r0, 1, 14 /* CC::al */, $noreg
-    tBX_RET 14 /* CC::al */, $noreg, implicit killed $r0
-
-...
-
-# CHECK-LABEL: name:            foo_sg
-# CHECK:       body:
-# CHECK-NEXT:   bb.0.entry:
-# CHECK-NEXT:     liveins: $r0
-# CHECK-NEXT:     {{^ +$}}
-# CHECK-NEXT:     t2SG