[llvm] 8a08740 - [GVN] Account for masked loads/stores depending on load/store instructions

[Krzysztof Parzyszek via llvm-commits]

Author: Krzysztof Parzyszek
Date: 2020-09-10T10:57:33-05:00
New Revision: 8a08740db6e13a3a36363c65b7e270cb7c66eb3c

URL: https://github.com/llvm/llvm-project/commit/8a08740db6e13a3a36363c65b7e270cb7c66eb3c
DIFF: https://github.com/llvm/llvm-project/commit/8a08740db6e13a3a36363c65b7e270cb7c66eb3c.diff

LOG: [GVN] Account for masked loads/stores depending on load/store instructions

This is a case where an intrinsic depends on a non-call instruction.

Differential Revision: https://reviews.llvm.org/D87423

Added: 
    llvm/test/Transforms/GVN/masked-load-store-vn-crash.ll

Modified: 
    llvm/lib/Transforms/Scalar/GVN.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Scalar/GVN.cpp b/llvm/lib/Transforms/Scalar/GVN.cpp
index 036ca1d1054f..2523cb178ddb 100644
--- a/llvm/lib/Transforms/Scalar/GVN.cpp
+++ b/llvm/lib/Transforms/Scalar/GVN.cpp
@@ -410,9 +410,12 @@ uint32_t GVN::ValueTable::lookupOrAddCall(CallInst *C) {
     }
 
     if (local_dep.isDef()) {
-      CallInst* local_cdep = cast<CallInst>(local_dep.getInst());
+      // For masked load/store intrinsics, the local_dep may actully be
+      // a normal load or store instruction.
+      CallInst *local_cdep = dyn_cast<CallInst>(local_dep.getInst());
 
-      if (local_cdep->getNumArgOperands() != C->getNumArgOperands()) {
+      if (!local_cdep ||
+          local_cdep->getNumArgOperands() != C->getNumArgOperands()) {
         valueNumbering[C] = nextValueNumber;
         return nextValueNumber++;
       }

diff  --git a/llvm/test/Transforms/GVN/masked-load-store-vn-crash.ll b/llvm/test/Transforms/GVN/masked-load-store-vn-crash.ll
new file mode 100644
index 000000000000..ae8369cd1945
--- /dev/null
+++ b/llvm/test/Transforms/GVN/masked-load-store-vn-crash.ll
@@ -0,0 +1,20 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -gvn -S < %s | FileCheck %s
+ at file_mask = external global [8 x i64], align 32
+
+define fastcc void @test() {
+; CHECK-LABEL: @test(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[WIDE_MASKED_LOAD_1_I:%.*]] = tail call <4 x i64> @llvm.masked.load.v4i64.p0v4i64(<4 x i64>* nonnull bitcast (i64* getelementptr inbounds ([8 x i64], [8 x i64]* @file_mask, i64 0, i64 7) to <4 x i64>*), i32 8, <4 x i1> <i1 true, i1 false, i1 false, i1 false>, <4 x i64> undef)
+; CHECK-NEXT:    unreachable
+;
+entry:
+  %wide.masked.load.1.i = tail call <4 x i64> @llvm.masked.load.v4i64.p0v4i64(<4 x i64>* nonnull bitcast (i64* getelementptr inbounds ([8 x i64], [8 x i64]* @file_mask, i64 0, i64 7) to <4 x i64>*), i32 8, <4 x i1> <i1 true, i1 false, i1 false, i1 false>, <4 x i64> undef) #2
+  %.pre392.i = load i64, i64* getelementptr inbounds ([8 x i64], [8 x i64]* @file_mask, i64 0, i64 7), align 8
+  %or156.4.i = or i64 %.pre392.i, undef
+  %wide.masked.load614.1.i = tail call <4 x i64> @llvm.masked.load.v4i64.p0v4i64(<4 x i64>* nonnull bitcast (i64* getelementptr inbounds ([8 x i64], [8 x i64]* @file_mask, i64 0, i64 7) to <4 x i64>*), i32 8, <4 x i1> <i1 true, i1 false, i1 false, i1 false>, <4 x i64> undef) #2
+  unreachable
+}
+
+; Function Attrs: argmemonly nounwind readonly willreturn
+declare <4 x i64> @llvm.masked.load.v4i64.p0v4i64(<4 x i64>*, i32 immarg, <4 x i1>, <4 x i64>)