[LoongArch] Fix out-of-range assert in DAG constant getting #141586
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
@llvm/pr-subscribers-backend-loongarch Author: hev (heiher) ChangesFixes #141583 Full diff: https://github.com/llvm/llvm-project/pull/141586.diff 2 Files Affected:
diff --git a/llvm/lib/Target/LoongArch/LoongArchISelLowering.cpp b/llvm/lib/Target/LoongArch/LoongArchISelLowering.cpp
index 9f5c94ddea44f..7a9ec9f5e96b3 100644
--- a/llvm/lib/Target/LoongArch/LoongArchISelLowering.cpp
+++ b/llvm/lib/Target/LoongArch/LoongArchISelLowering.cpp
@@ -4410,7 +4410,7 @@ static SDValue performORCombine(SDNode *N, SelectionDAG &DAG,
LLVM_DEBUG(dbgs() << "Perform OR combine: match pattern 5\n");
return DAG.getNode(
LoongArchISD::BSTRINS, DL, ValTy, N0.getOperand(0),
- DAG.getConstant(CN1->getSExtValue() >> MaskIdx0, DL, ValTy),
+ DAG.getSignedConstant(CN1->getSExtValue() >> MaskIdx0, DL, ValTy),
DAG.getConstant(ValBits == 32 ? (MaskIdx0 + (MaskLen0 & 31) - 1)
: (MaskIdx0 + MaskLen0 - 1),
DL, GRLenVT),
diff --git a/llvm/test/CodeGen/LoongArch/bstrins_w.ll b/llvm/test/CodeGen/LoongArch/bstrins_w.ll
index c59f15bd64112..0fea0470394d2 100644
--- a/llvm/test/CodeGen/LoongArch/bstrins_w.ll
+++ b/llvm/test/CodeGen/LoongArch/bstrins_w.ll
@@ -207,6 +207,18 @@ define i32 @pat8(i32 %c) nounwind {
ret i32 %or
}
+define i32 @pat9(i32 %a) {
+; CHECK-LABEL: pat9:
+; CHECK: # %bb.0:
+; CHECK-NEXT: lu12i.w $a1, -8
+; CHECK-NEXT: ori $a1, $a1, 564
+; CHECK-NEXT: bstrins.w $a0, $a1, 31, 16
+; CHECK-NEXT: ret
+ %and = and i32 %a, 65535 ; 0x0000ffff
+ %or = or i32 %and, -2110521344 ; 0x82340000
+ ret i32 %or
+}
+
;; Test that bstrins.w is not generated because constant OR operand
;; doesn't fit into bits cleared by constant AND operand.
define i32 @no_bstrins_w(i32 %a) nounwind {
|
SixWeining
reviewed
May 27, 2025
| @@ -4410,7 +4410,7 @@ static SDValue performORCombine(SDNode *N, SelectionDAG &DAG, | |||
| LLVM_DEBUG(dbgs() << "Perform OR combine: match pattern 5\n"); | |||
| return DAG.getNode( | |||
| LoongArchISD::BSTRINS, DL, ValTy, N0.getOperand(0), | |||
| DAG.getConstant(CN1->getSExtValue() >> MaskIdx0, DL, ValTy), | |||
| DAG.getSignedConstant(CN1->getSExtValue() >> MaskIdx0, DL, ValTy), | |||
There was a problem hiding this comment.
Do other calls to DAG.getConstant() have the same issue?
There was a problem hiding this comment.
Perhaps. I haven't found any others so far, but if I do, I might fix them in this PR or in a follow-up.
There was a problem hiding this comment.
I came across a few more spots that might be risky, based on the data types and value ranges of getConstant() and getTargetConstant(). I’ll include defensive fixes in this PR, but given the low risk and similarity of the cases, I’m not planning to add separate tests for each one.
heiher
changed the title
SixWeining
approved these changes
May 28, 2025
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/141/builds/9066 Here is the relevant piece of the build log for the reference |
sivan-shani
pushed a commit
to sivan-shani/llvm-project
that referenced
this pull request
Jun 3, 2025
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Fixes #141583