[llvm] afe9264 - Revert "[CaptureTracking] Avoid overly restrictive dominates check"
Anna Thomas via llvm-commits
llvm-commits at lists.llvm.org
Thu Nov 5 09:27:22 PST 2020
Author: Anna Thomas
Date: 2020-11-05T12:27:15-05:00
New Revision: afe92642cc73db48ea46a1dc1a534492249040a7
URL: https://github.com/llvm/llvm-project/commit/afe92642cc73db48ea46a1dc1a534492249040a7
DIFF: https://github.com/llvm/llvm-project/commit/afe92642cc73db48ea46a1dc1a534492249040a7.diff
LOG: Revert "[CaptureTracking] Avoid overly restrictive dominates check"
This reverts commit 15694fd6ad955c6a16b446a6324364111a49ae8b.
Need to investigate and fix a failing clang test: synchronized.m.
Might need a test update.
Added:
Modified:
llvm/lib/Analysis/CaptureTracking.cpp
llvm/test/Transforms/MemCpyOpt/callslot.ll
Removed:
################################################################################
diff --git a/llvm/lib/Analysis/CaptureTracking.cpp b/llvm/lib/Analysis/CaptureTracking.cpp
index 15e022c64402..06a3b81e0362 100644
--- a/llvm/lib/Analysis/CaptureTracking.cpp
+++ b/llvm/lib/Analysis/CaptureTracking.cpp
@@ -133,10 +133,10 @@ namespace {
return !isPotentiallyReachableFromMany(Worklist, BB, nullptr, DT);
}
- // If the value is defined in a
diff erent basic block than BeforeHere,
- // there is no need to explore the use if there is no path from I to
- // BeforeHere.
- if (BeforeHere != I &&
+ // If the value is defined in the same basic block as use and BeforeHere,
+ // there is no need to explore the use if BeforeHere dominates use.
+ // Check whether there is a path from I to BeforeHere.
+ if (BeforeHere != I && DT->dominates(BeforeHere, I) &&
!isPotentiallyReachable(I, BeforeHere, nullptr, DT))
return true;
diff --git a/llvm/test/Transforms/MemCpyOpt/callslot.ll b/llvm/test/Transforms/MemCpyOpt/callslot.ll
index c9d23644cf51..f85a67667950 100644
--- a/llvm/test/Transforms/MemCpyOpt/callslot.ll
+++ b/llvm/test/Transforms/MemCpyOpt/callslot.ll
@@ -186,39 +186,6 @@ define void @capture_before_call_argmemonly() {
ret void
}
-; There is no path from the capture back to the memcpy.
-; So we can perform the call slot optimization.
-define void @capture_nopath_call_argmemonly(i1 %cond) {
-; CHECK-LABEL: @capture_nopath_call_argmemonly(
-; CHECK-NEXT: [[DEST:%.*]] = alloca [16 x i8], align 1
-; CHECK-NEXT: [[SRC:%.*]] = alloca [16 x i8], align 1
-; CHECK-NEXT: [[DEST_I8:%.*]] = bitcast [16 x i8]* [[DEST]] to i8*
-; CHECK-NEXT: [[SRC_I8:%.*]] = bitcast [16 x i8]* [[SRC]] to i8*
-; CHECK-NEXT: br i1 [[COND:%.*]], label [[CAPTURES:%.*]], label [[NOCAPTURES:%.*]]
-; CHECK: captures:
-; CHECK-NEXT: call void @accept_ptr(i8* [[DEST_I8]])
-; CHECK-NEXT: ret void
-; CHECK: nocaptures:
-; CHECK-NEXT: [[DEST1:%.*]] = bitcast [16 x i8]* [[DEST]] to i8*
-; CHECK-NEXT: call void @accept_ptr(i8* [[DEST1]]) [[ATTR5:#.*]]
-; CHECK-NEXT: ret void
-;
- %dest = alloca [16 x i8]
- %src = alloca [16 x i8]
- %dest.i8 = bitcast [16 x i8]* %dest to i8*
- %src.i8 = bitcast [16 x i8]* %src to i8*
- br i1 %cond, label %captures, label %nocaptures
-
-captures:
- call void @accept_ptr(i8* %dest.i8) ; capture
- ret void
-
-nocaptures:
- call void @accept_ptr(i8* %src.i8) argmemonly nounwind
- call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dest.i8, i8* %src.i8, i64 16, i1 false)
- ret void
-}
-
define void @capture_before_call_argmemonly_nounwind() {
; CHECK-LABEL: @capture_before_call_argmemonly_nounwind(
; CHECK-NEXT: [[DEST:%.*]] = alloca [16 x i8], align 1
More information about the llvm-commits
mailing list