[PATCH] D122929: [BOLT] Fix remove double jumps peephole pass

[Vladislav Khmelevsky via Phabricator via llvm-commits]

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Remove the assert statement and change the if condition since it does
not cover non-local branch cases.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D122929

Files:
  bolt/lib/Passes/BinaryPasses.cpp
  bolt/test/AArch64/ext-double-jump.s


Index: bolt/test/AArch64/ext-double-jump.s
===================================================================
--- /dev/null
+++ bolt/test/AArch64/ext-double-jump.s
@@ -0,0 +1,26 @@
+# RUN: llvm-mc -filetype=obj -triple aarch64-unknown-unknown \
+# RUN:   %s -o %t.o
+# RUN: %clang %cflags -nostartfiles -nodefaultlibs %t.o -o %t.exe -Wl,-q
+# RUN: llvm-bolt %t.exe -o %t.bolt -peepholes=double-jumps
+
+  .text
+  .align 4
+  .global dummy1
+  .type dummy1, %function
+dummy1:
+  mov x2, x0
+  ret
+
+  .global dummy2
+  .type dummy2, %function
+dummy2:
+  mov x1, x0
+  ret
+
+  .global _start
+  .type _start, %function
+_start:
+  cbz  x10, 1f
+  b dummy1
+1:
+  b dummy2
Index: bolt/lib/Passes/BinaryPasses.cpp
===================================================================
--- bolt/lib/Passes/BinaryPasses.cpp
+++ bolt/lib/Passes/BinaryPasses.cpp
@@ -697,8 +697,8 @@
         // Succ will be null in the tail call case.  In this case we
         // need to explicitly add a tail call instruction.
         MCInst *Branch = Pred->getLastNonPseudoInstr();
-        if (Branch && MIB->isUnconditionalBranch(*Branch)) {
-          assert(MIB->getTargetSymbol(*Branch) == BB.getLabel());
+        if (Branch && MIB->isUnconditionalBranch(*Branch) &&
+            MIB->getTargetSymbol(*Branch) == BB.getLabel()) {
           Pred->removeSuccessor(&BB);
           Pred->eraseInstruction(Pred->findInstruction(Branch));
           Pred->addTailCallInstruction(SuccSym);


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