[llvm] 6c7957c - [SVE] Fix bug in SVEIntrinsicOpts::optimizePTest

[David Sherwood via llvm-commits]

Author: David Sherwood
Date: 2020-08-14T07:57:21+01:00
New Revision: 6c7957c9901714b7ad0a8d2743a8c431b57fd0c9

URL: https://github.com/llvm/llvm-project/commit/6c7957c9901714b7ad0a8d2743a8c431b57fd0c9
DIFF: https://github.com/llvm/llvm-project/commit/6c7957c9901714b7ad0a8d2743a8c431b57fd0c9.diff

LOG: [SVE] Fix bug in SVEIntrinsicOpts::optimizePTest

The code wasn't taking into account that the two operands
passed to ptest could be identical and was trying to erase
them twice.

Differential Revision: https://reviews.llvm.org/D85892

Added: 
    

Modified: 
    llvm/lib/Target/AArch64/SVEIntrinsicOpts.cpp
    llvm/test/CodeGen/AArch64/sve-intrinsic-opts-ptest.ll

Removed: 
    


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diff  --git a/llvm/lib/Target/AArch64/SVEIntrinsicOpts.cpp b/llvm/lib/Target/AArch64/SVEIntrinsicOpts.cpp
index 542d2c964515..67fc4ee0a29d 100644
--- a/llvm/lib/Target/AArch64/SVEIntrinsicOpts.cpp
+++ b/llvm/lib/Target/AArch64/SVEIntrinsicOpts.cpp
@@ -160,7 +160,7 @@ bool SVEIntrinsicOpts::optimizePTest(IntrinsicInst *I) {
     I->eraseFromParent();
     if (Op1->use_empty())
       Op1->eraseFromParent();
-    if (Op2->use_empty())
+    if (Op1 != Op2 && Op2->use_empty())
       Op2->eraseFromParent();
 
     return true;

diff  --git a/llvm/test/CodeGen/AArch64/sve-intrinsic-opts-ptest.ll b/llvm/test/CodeGen/AArch64/sve-intrinsic-opts-ptest.ll
index 96c754778d52..ba66323439cc 100644
--- a/llvm/test/CodeGen/AArch64/sve-intrinsic-opts-ptest.ll
+++ b/llvm/test/CodeGen/AArch64/sve-intrinsic-opts-ptest.ll
@@ -44,6 +44,16 @@ define i1 @ptest_first(<vscale x 4 x i1> %a) {
   ret i1 %out
 }
 
+define i1 @ptest_first_same_ops(<vscale x 2 x i1> %a) {
+; OPT-LABEL: ptest_first_same_ops
+; OPT: %[[OUT:.*]] = call i1 @llvm.aarch64.sve.ptest.first.nxv2i1(<vscale x 2 x i1> %a, <vscale x 2 x i1> %a)
+; OPT-NOT: convert
+; OPT-NEXT: ret i1 %[[OUT]]
+  %1 = tail call <vscale x 16 x i1> @llvm.aarch64.sve.convert.to.svbool.nxv2i1(<vscale x 2 x i1> %a)
+  %2 = tail call i1 @llvm.aarch64.sve.ptest.first.nxv16i1(<vscale x 16 x i1> %1, <vscale x 16 x i1> %1)
+  ret i1 %2
+}
+
 define i1 @ptest_last(<vscale x 8 x i1> %a) {
 ; OPT-LABEL: ptest_last
 ; OPT: %mask = tail call <vscale x 8 x i1> @llvm.aarch64.sve.ptrue.nxv8i1(i32 0)