[llvm] r314927 - [TargetTransformInfo] Check if function pointer is valid before calling isLoweredToCall

[Guozhi Wei via llvm-commits]

Author: carrot
Date: Wed Oct  4 13:14:08 2017
New Revision: 314927

URL: http://llvm.org/viewvc/llvm-project?rev=314927&view=rev
Log:
[TargetTransformInfo] Check if function pointer is valid before calling isLoweredToCall

Function isLoweredToCall can only accept non-null function pointer, but a function pointer can be null for indirect function call. So check it before calling isLoweredToCall from getInstructionLatency.

Differential Revision: https://reviews.llvm.org/D38204


Modified:
    llvm/trunk/include/llvm/Analysis/TargetTransformInfoImpl.h
    llvm/trunk/test/Analysis/CostModel/X86/costmodel.ll

Modified: llvm/trunk/include/llvm/Analysis/TargetTransformInfoImpl.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/TargetTransformInfoImpl.h?rev=314927&r1=314926&r2=314927&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/TargetTransformInfoImpl.h (original)
+++ llvm/trunk/include/llvm/Analysis/TargetTransformInfoImpl.h Wed Oct  4 13:14:08 2017
@@ -188,6 +188,8 @@ public:
   }
 
   bool isLoweredToCall(const Function *F) {
+    assert(F && "A concrete function must be provided to this routine.");
+
     // FIXME: These should almost certainly not be handled here, and instead
     // handled with the help of TLI or the target itself. This was largely
     // ported from existing analysis heuristics here so that such refactorings
@@ -828,7 +830,7 @@ public:
     // A real function call is much slower.
     if (auto *CI = dyn_cast<CallInst>(I)) {
       const Function *F = CI->getCalledFunction();
-      if (static_cast<T *>(this)->isLoweredToCall(F))
+      if (!F || static_cast<T *>(this)->isLoweredToCall(F))
         return 40;
       // Some intrinsics return a value and a flag, we use the value type
       // to decide its latency.

Modified: llvm/trunk/test/Analysis/CostModel/X86/costmodel.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Analysis/CostModel/X86/costmodel.ll?rev=314927&r1=314926&r2=314927&view=diff
==============================================================================
--- llvm/trunk/test/Analysis/CostModel/X86/costmodel.ll (original)
+++ llvm/trunk/test/Analysis/CostModel/X86/costmodel.ll Wed Oct  4 13:14:08 2017
@@ -45,6 +45,10 @@ define i64 @foo(i64 %arg) {
   ; CODESIZE: cost of 1 {{.*}} call
   %uadd = call { i32, i1 } @llvm.uadd.with.overflow.i32(i32 undef, i32 undef)
 
+  ; LATENCY:  cost of 40 {{.*}} call void undef
+  ; CODESIZE: cost of 1 {{.*}} call void undef
+  call void undef()
+
   ; LATENCY:  cost of 1 {{.*}} ret
   ; CODESIZE: cost of 1 {{.*}} ret
   ret i64 undef