[llvm-branch-commits] [llvm] 1a497ae - [ARM][Block placement] Check the predecessor exists before processing it
Sam Tebbs via llvm-branch-commits
llvm-branch-commits at lists.llvm.org
Fri Jan 15 07:49:23 PST 2021
Author: Sam Tebbs
Date: 2021-01-15T15:45:13Z
New Revision: 1a497ae9b83653682d6d20f1ec131394e523375d
URL: https://github.com/llvm/llvm-project/commit/1a497ae9b83653682d6d20f1ec131394e523375d
DIFF: https://github.com/llvm/llvm-project/commit/1a497ae9b83653682d6d20f1ec131394e523375d.diff
LOG: [ARM][Block placement] Check the predecessor exists before processing it
Not all machine loops will have a predecessor. so the pass needs to
check it before continuing.
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D94780
Added:
Modified:
llvm/lib/Target/ARM/ARMBlockPlacement.cpp
llvm/test/CodeGen/Thumb2/block-placement.mir
Removed:
################################################################################
diff --git a/llvm/lib/Target/ARM/ARMBlockPlacement.cpp b/llvm/lib/Target/ARM/ARMBlockPlacement.cpp
index 20491273ea5d4..581b4b9857af3 100644
--- a/llvm/lib/Target/ARM/ARMBlockPlacement.cpp
+++ b/llvm/lib/Target/ARM/ARMBlockPlacement.cpp
@@ -79,6 +79,8 @@ bool ARMBlockPlacement::runOnMachineFunction(MachineFunction &MF) {
// LE branch then move the target block after the preheader.
for (auto *ML : *MLI) {
MachineBasicBlock *Preheader = ML->getLoopPredecessor();
+ if (!Preheader)
+ continue;
for (auto &Terminator : Preheader->terminators()) {
if (Terminator.getOpcode() != ARM::t2WhileLoopStart)
diff --git a/llvm/test/CodeGen/Thumb2/block-placement.mir b/llvm/test/CodeGen/Thumb2/block-placement.mir
index d96a1fb49abbb..ed4a0a6b493d8 100644
--- a/llvm/test/CodeGen/Thumb2/block-placement.mir
+++ b/llvm/test/CodeGen/Thumb2/block-placement.mir
@@ -25,6 +25,16 @@
entry:
unreachable
}
+
+ define void @no_preheader(i32 %N, i32 %M, i32* nocapture %a, i32* nocapture %b, i32* nocapture %c) local_unnamed_addr #0 {
+ entry:
+ unreachable
+ }
+
+ declare dso_local i32 @g(...) local_unnamed_addr #1
+
+ declare dso_local i32 @h(...) local_unnamed_addr #1
+
...
---
name: backwards_branch
@@ -343,3 +353,91 @@ body: |
t2B %bb.1, 14 /* CC::al */, $noreg
...
+---
+name: no_preheader
+body: |
+ ; CHECK-LABEL: name: no_preheader
+ ; CHECK: bb.0:
+ ; CHECK: successors: %bb.2(0x30000000), %bb.1(0x50000000)
+ ; CHECK: frame-setup tPUSH 14 /* CC::al */, $noreg, killed $r4, killed $r5, $r7, killed $lr, implicit-def $sp, implicit $sp
+ ; CHECK: frame-setup CFI_INSTRUCTION def_cfa_offset 16
+ ; CHECK: frame-setup CFI_INSTRUCTION offset $lr, -4
+ ; CHECK: frame-setup CFI_INSTRUCTION offset $r7, -8
+ ; CHECK: frame-setup CFI_INSTRUCTION offset $r5, -12
+ ; CHECK: frame-setup CFI_INSTRUCTION offset $r4, -16
+ ; CHECK: $r7 = frame-setup tADDrSPi $sp, 2, 14 /* CC::al */, $noreg
+ ; CHECK: frame-setup CFI_INSTRUCTION def_cfa $r7, 8
+ ; CHECK: $r4 = tMOVr killed $r0, 14 /* CC::al */, $noreg
+ ; CHECK: tBL 14 /* CC::al */, $noreg, @g, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit-def $sp, implicit-def $r0
+ ; CHECK: tCMPi8 killed renamable $r0, 0, 14 /* CC::al */, $noreg, implicit-def $cpsr
+ ; CHECK: t2Bcc %bb.2, 0 /* CC::eq */, killed $cpsr
+ ; CHECK: bb.1:
+ ; CHECK: successors: %bb.4(0x80000000)
+ ; CHECK: renamable $r0, dead $cpsr = tMOVi8 4, 14 /* CC::al */, $noreg
+ ; CHECK: renamable $r5 = t2LDRSHi12 killed renamable $r0, 0, 14 /* CC::al */, $noreg
+ ; CHECK: t2B %bb.4, 14 /* CC::al */, $noreg
+ ; CHECK: bb.2:
+ ; CHECK: successors: %bb.4(0x80000000)
+ ; CHECK: renamable $r5, dead $cpsr = tMOVi8 0, 14 /* CC::al */, $noreg
+ ; CHECK: t2B %bb.4, 14 /* CC::al */, $noreg
+ ; CHECK: bb.3:
+ ; CHECK: successors: %bb.4(0x80000000)
+ ; CHECK: $r0 = tMOVr $r5, 14 /* CC::al */, $noreg
+ ; CHECK: tBL 14 /* CC::al */, $noreg, @h, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $r0, implicit-def $sp, implicit-def dead $r0
+ ; CHECK: bb.4:
+ ; CHECK: successors: %bb.5(0x04000000), %bb.3(0x7c000000)
+ ; CHECK: renamable $r0 = tLDRi renamable $r4, 0, 14 /* CC::al */, $noreg
+ ; CHECK: tCMPi8 killed renamable $r0, 0, 14 /* CC::al */, $noreg, implicit-def $cpsr
+ ; CHECK: t2Bcc %bb.3, 1 /* CC::ne */, killed $cpsr
+ ; CHECK: bb.5:
+ ; CHECK: frame-destroy tPOP_RET 14 /* CC::al */, $noreg, def $r4, def $r5, def $r7, def $pc
+ bb.0:
+ successors: %bb.1(0x30000000), %bb.2(0x50000000)
+ liveins: $r0, $r4, $r5, $lr
+
+ frame-setup tPUSH 14 /* CC::al */, $noreg, killed $r4, killed $r5, $r7, killed $lr, implicit-def $sp, implicit $sp
+ frame-setup CFI_INSTRUCTION def_cfa_offset 16
+ frame-setup CFI_INSTRUCTION offset $lr, -4
+ frame-setup CFI_INSTRUCTION offset $r7, -8
+ frame-setup CFI_INSTRUCTION offset $r5, -12
+ frame-setup CFI_INSTRUCTION offset $r4, -16
+ $r7 = frame-setup tADDrSPi $sp, 2, 14 /* CC::al */, $noreg
+ frame-setup CFI_INSTRUCTION def_cfa $r7, 8
+ $r4 = tMOVr killed $r0, 14 /* CC::al */, $noreg
+ tBL 14 /* CC::al */, $noreg, @g, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit-def $sp, implicit-def $r0
+ tCMPi8 killed renamable $r0, 0, 14 /* CC::al */, $noreg, implicit-def $cpsr
+ t2Bcc %bb.1, 0 /* CC::eq */, killed $cpsr
+
+ bb.2:
+ successors: %bb.3(0x80000000)
+ liveins: $r4
+
+ renamable $r0, dead $cpsr = tMOVi8 4, 14 /* CC::al */, $noreg
+ renamable $r5 = t2LDRSHi12 killed renamable $r0, 0, 14 /* CC::al */, $noreg
+ t2B %bb.3, 14 /* CC::al */, $noreg
+
+ bb.1:
+ successors: %bb.3(0x80000000)
+ liveins: $r4
+
+ renamable $r5, dead $cpsr = tMOVi8 0, 14 /* CC::al */, $noreg
+ t2B %bb.3, 14 /* CC::al */, $noreg
+
+ bb.4:
+ successors: %bb.3(0x80000000)
+ liveins: $r4, $r5
+
+ $r0 = tMOVr $r5, 14 /* CC::al */, $noreg
+ tBL 14 /* CC::al */, $noreg, @h, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $r0, implicit-def $sp, implicit-def dead $r0
+
+ bb.3:
+ successors: %bb.5(0x04000000), %bb.4(0x7c000000)
+ liveins: $r4, $r5
+
+ renamable $r0 = tLDRi renamable $r4, 0, 14 /* CC::al */, $noreg
+ tCMPi8 killed renamable $r0, 0, 14 /* CC::al */, $noreg, implicit-def $cpsr
+ t2Bcc %bb.4, 1 /* CC::ne */, killed $cpsr
+
+ bb.5:
+ frame-destroy tPOP_RET 14 /* CC::al */, $noreg, def $r4, def $r5, def $r7, def $pc
+...
More information about the llvm-branch-commits
mailing list