[llvm] 41ba801 - [CallSite Removal] a CallBase is never an IndirectCall for isInlineAsm

[Nick Desaulniers via llvm-commits]

Author: Nick Desaulniers
Date: 2020-04-06T16:14:46-07:00
New Revision: 41ba80182cc2540fcf85bcda10bbde04816b7e6e

URL: https://github.com/llvm/llvm-project/commit/41ba80182cc2540fcf85bcda10bbde04816b7e6e
DIFF: https://github.com/llvm/llvm-project/commit/41ba80182cc2540fcf85bcda10bbde04816b7e6e.diff

LOG: [CallSite Removal] a CallBase is never an IndirectCall for isInlineAsm

Summary:
Thanks to Bill Wendling (void) for the report and steps to reproduce.  It looks
like this was missed during r350508's cleanup of the CallSite split into
CallBase, CallInst, and CallBrInst.

This was exposed by running pgo on a callbr, which was creating a ptrtoint to
the inline asm thinking it was an indirect call. The relevant callchain looks
like:

    IndirectCallPromotionPlugin::run()
    -> PGOIndirectCallVisitor::findIndirectCalls()
      -> PGOIndirectCallVisitor::visitCallBase()
        -> CallBase::isIndirectCall()

Reviewers: void, chandlerc

Reviewed By: void

Subscribers: hiraditya, llvm-commits, craig.topper, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77600

Added: 
    llvm/test/Transforms/PGOProfile/callbr.ll

Modified: 
    llvm/lib/IR/Instructions.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/IR/Instructions.cpp b/llvm/lib/IR/Instructions.cpp
index 37e194a0feab..3e1639b338f8 100644
--- a/llvm/lib/IR/Instructions.cpp
+++ b/llvm/lib/IR/Instructions.cpp
@@ -267,10 +267,7 @@ bool CallBase::isIndirectCall() const {
   const Value *V = getCalledValue();
   if (isa<Function>(V) || isa<Constant>(V))
     return false;
-  if (const CallInst *CI = dyn_cast<CallInst>(this))
-    if (CI->isInlineAsm())
-      return false;
-  return true;
+  return !isInlineAsm();
 }
 
 /// Tests if this call site must be tail call optimized. Only a CallInst can

diff  --git a/llvm/test/Transforms/PGOProfile/callbr.ll b/llvm/test/Transforms/PGOProfile/callbr.ll
new file mode 100644
index 000000000000..626b7741fa83
--- /dev/null
+++ b/llvm/test/Transforms/PGOProfile/callbr.ll
@@ -0,0 +1,17 @@
+; RUN: opt -pgo-instr-gen -S 2>&1 < %s | FileCheck %s
+
+define i32 @a() {
+entry:
+; CHECK-NOT: ptrtoint void (i8*)* asm sideeffect
+; CHECK: callbr void asm sideeffect
+  %retval = alloca i32, align 4
+  callbr void asm sideeffect "", "X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@a, %b)) #1
+          to label %asm.fallthrough [label %b]
+
+asm.fallthrough:
+  br label %b
+
+b:
+  %0 = load i32, i32* %retval, align 4
+  ret i32 %0
+}