/
cherry-pick-1234770.patch
75 lines (69 loc) · 2.98 KB
/
cherry-pick-1234770.patch
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Georg Neis <neis@chromium.org>
Date: Mon, 9 Aug 2021 09:57:12 +0200
Subject: Merged: [compiler] Fix a bug in MachineOperatorReducer's
BitfieldCheck
Revision: 574ca6b71c6160d38b5fcf4b8e133bc7f6ba2387
BUG=chromium:1234770
NOTRY=true
NOPRESUBMIT=true
NOTREECHECKS=true
R=nicohartmann@chromium.org
Change-Id: I15af5a94e89b54c2a540442c3544ed459b832e0a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3080564
Reviewed-by: Lutz Vahl <vahl@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/branch-heads/9.3@{#21}
Cr-Branched-From: 7744dce208a555494e4a33e24fadc71ea20b3895-refs/heads/9.3.345@{#1}
Cr-Branched-From: 4b6b4cabf3b6a20cdfda72b369df49f3311c4344-refs/heads/master@{#75728}
diff --git a/src/compiler/machine-operator-reducer.cc b/src/compiler/machine-operator-reducer.cc
index 5d61dfac6ab46687b0adde2ff9777a0252e16494..b4b16f931f0927e9b683f38b393b0d275727f25e 100644
--- a/src/compiler/machine-operator-reducer.cc
+++ b/src/compiler/machine-operator-reducer.cc
@@ -1718,11 +1718,21 @@ Reduction MachineOperatorReducer::ReduceWordNAnd(Node* node) {
namespace {
// Represents an operation of the form `(source & mask) == masked_value`.
+// where each bit set in masked_value also has to be set in mask.
struct BitfieldCheck {
- Node* source;
- uint32_t mask;
- uint32_t masked_value;
- bool truncate_from_64_bit;
+ Node* const source;
+ uint32_t const mask;
+ uint32_t const masked_value;
+ bool const truncate_from_64_bit;
+
+ BitfieldCheck(Node* source, uint32_t mask, uint32_t masked_value,
+ bool truncate_from_64_bit)
+ : source(source),
+ mask(mask),
+ masked_value(masked_value),
+ truncate_from_64_bit(truncate_from_64_bit) {
+ CHECK_EQ(masked_value & ~mask, 0);
+ }
static base::Optional<BitfieldCheck> Detect(Node* node) {
// There are two patterns to check for here:
@@ -1737,14 +1747,16 @@ struct BitfieldCheck {
if (eq.left().IsWord32And()) {
Uint32BinopMatcher mand(eq.left().node());
if (mand.right().HasResolvedValue() && eq.right().HasResolvedValue()) {
- BitfieldCheck result{mand.left().node(), mand.right().ResolvedValue(),
- eq.right().ResolvedValue(), false};
+ uint32_t mask = mand.right().ResolvedValue();
+ uint32_t masked_value = eq.right().ResolvedValue();
+ if ((masked_value & ~mask) != 0) return {};
if (mand.left().IsTruncateInt64ToInt32()) {
- result.truncate_from_64_bit = true;
- result.source =
- NodeProperties::GetValueInput(mand.left().node(), 0);
+ return BitfieldCheck(
+ NodeProperties::GetValueInput(mand.left().node(), 0), mask,
+ masked_value, true);
+ } else {
+ return BitfieldCheck(mand.left().node(), mask, masked_value, false);
}
- return result;
}
}
} else {