[llvm] 2ba06be - Revert "StackProtector: ignore debug insts when splitting blocks."

[Tim Northover via llvm-commits]

Author: Tim Northover
Date: 2022-02-11T18:06:28Z
New Revision: 2ba06bed6b1eda41ad2cc9a16392f770f1bf0bcc

URL: https://github.com/llvm/llvm-project/commit/2ba06bed6b1eda41ad2cc9a16392f770f1bf0bcc
DIFF: https://github.com/llvm/llvm-project/commit/2ba06bed6b1eda41ad2cc9a16392f770f1bf0bcc.diff

LOG: Revert "StackProtector: ignore debug insts when splitting blocks."

This reverts commit 7605ca85f1a8e4e61e7de98856630d67da11aaae.

It caused an assertion failure in Fuschia.

Added: 
    

Modified: 
    llvm/lib/CodeGen/CodeGenCommonISel.cpp

Removed: 
    llvm/test/CodeGen/AArch64/tailcall-ssp-split-debug.ll


################################################################################
diff  --git a/llvm/lib/CodeGen/CodeGenCommonISel.cpp b/llvm/lib/CodeGen/CodeGenCommonISel.cpp
index f809120f02faf..877aa69c3e58b 100644
--- a/llvm/lib/CodeGen/CodeGenCommonISel.cpp
+++ b/llvm/lib/CodeGen/CodeGenCommonISel.cpp
@@ -129,9 +129,7 @@ llvm::findSplitPointForStackProtector(MachineBasicBlock *BB,
 
   MachineBasicBlock::iterator Start = BB->begin();
   MachineBasicBlock::iterator Previous = SplitPoint;
-  do {
-    --Previous;
-  } while (Previous->isDebugInstr());
+  --Previous;
 
   if (TII.isTailCall(*SplitPoint) &&
       Previous->getOpcode() == TII.getCallFrameDestroyOpcode()) {
@@ -144,7 +142,7 @@ llvm::findSplitPointForStackProtector(MachineBasicBlock *BB,
     //     ADJCALLSTACKUP ...
     //     TAILJMP somewhere
     // On the other hand, it could be an unrelated call in which case this tail
-    // call has no register moves of its own and should be the split point. For
+    // call has to register moves of its own and should be the split point. For
     // example:
     //     ADJCALLSTACKDOWN
     //     CALL something_else

diff  --git a/llvm/test/CodeGen/AArch64/tailcall-ssp-split-debug.ll b/llvm/test/CodeGen/AArch64/tailcall-ssp-split-debug.ll
deleted file mode 100644
index b439fdbeb0dae..0000000000000
--- a/llvm/test/CodeGen/AArch64/tailcall-ssp-split-debug.ll
+++ /dev/null
@@ -1,40 +0,0 @@
-; RUN: llc -mtriple=arm64-apple-ios %s -o - | FileCheck %s
-
-define swifttailcc void @foo(i8* %call) ssp {
-; CHECK-LABEL: foo:
-  %var = alloca [28 x i8], align 16
-  br i1 undef, label %if.then, label %if.end
-
-if.then:
-  ret void
-
-if.end:
-  ; CHECK: mov x[[NULL:[0-9]+]], xzr
-  ; CHECK: ldr [[FPTR:x[0-9]+]], [x[[NULL]]]
-  ; CHECK: br [[FPTR]]
-  call void @llvm.dbg.value(metadata i8* %call, metadata !19, metadata !DIExpression()), !dbg !21
-  %fptr = load void (i8*)*, void (i8*)** null, align 8
-  musttail call swifttailcc void %fptr(i8* null)
-  ret void
-}
-
-declare i8* @pthread_getspecific()
-
-; Function Attrs: nofree nosync nounwind readnone speculatable willreturn
-declare void @llvm.dbg.value(metadata, metadata, metadata) #1
-
-!llvm.module.flags = !{!2}
-!llvm.dbg.cu = !{!11}
-
-!2 = !{i32 2, !"Debug Info Version", i32 3}
-!11 = distinct !DICompileUnit(language: DW_LANG_C99, file: !12, producer: "Apple clang version 13.1.6 (clang-1316.0.17.4)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !13, splitDebugInlining: false, nameTableKind: None, sysroot: "/Library/Developer/CommandLineTools/SDKs/MacOSX12.3.sdk", sdk: "MacOSX12.3.sdk")
-!12 = !DIFile(filename: "tmp.c", directory: "/Users/tim/llvm-internal/llvm-project/build")
-!13 = !{}
-!14 = !{!"Apple clang version 13.1.6 (clang-1316.0.17.4)"}
-!15 = distinct !DISubprogram(name: "bar", scope: !12, file: !12, line: 3, type: !16, scopeLine: 3, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !11, retainedNodes: !18)
-!16 = !DISubroutineType(types: !17)
-!17 = !{null}
-!18 = !{!19}
-!19 = !DILocalVariable(name: "var", scope: !15, file: !12, line: 4, type: !20)
-!20 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
-!21 = !DILocation(line: 0, scope: !15)