-
-
Notifications
You must be signed in to change notification settings - Fork 5.4k
/
llvm-D14260.patch
136 lines (134 loc) · 4.72 KB
/
llvm-D14260.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
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
Index: lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
===================================================================
--- a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -879,6 +879,61 @@
return nullptr;
}
+/// \brief Look for extractelement/insertvalue sequence that acts like a bitcast.
+///
+/// \returns underlying value that was "cast", or nullptr otherwise.
+///
+/// For example, if we have:
+///
+/// %E0 = extractelement <2 x double> %U, i32 0
+/// %V0 = insertvalue [2 x double] undef, double %E0, 0
+/// %E1 = extractelement <2 x double> %U, i32 1
+/// %V1 = insertvalue [2 x double] %V0, double %E1, 1
+///
+/// and the layout of a <2 x double> is isomorphic to a [2 x double],
+/// then %V1 can be safely approximated by a conceptual "bitcast" of %U.
+/// Note that %U may contain non-undef values where %V1 has undef.
+static Value* likeBitCastFromVector(InstCombiner &IC, Value* V) {
+ Value *U = nullptr;
+ while (auto *IV = dyn_cast<InsertValueInst>(V)) {
+ auto *E = dyn_cast<ExtractElementInst>(IV->getInsertedValueOperand());
+ if (!E)
+ return nullptr;
+ auto *W = E->getVectorOperand();
+ if (!U)
+ U = W;
+ else if (U != W)
+ return nullptr;
+ auto *CI = dyn_cast<ConstantInt>(E->getIndexOperand());
+ if (!CI || IV->getNumIndices() != 1 || CI->getZExtValue() != *IV->idx_begin())
+ return nullptr;
+ V = IV->getAggregateOperand();
+ }
+ if (!isa<UndefValue>(V) ||!U)
+ return nullptr;
+
+ VectorType *UT = cast<VectorType>(U->getType());
+ Type *VT = V->getType();
+ // Check that types UT and VT are bitwise isomorphic.
+ const DataLayout &DL = IC.getDataLayout();
+ if (DL.getTypeSizeInBits(UT) != DL.getTypeSizeInBits(VT)) {
+ return nullptr;
+ }
+ if (ArrayType *AT = dyn_cast<ArrayType>(VT)) {
+ if (AT->getNumElements() != UT->getNumElements())
+ return nullptr;
+ } else {
+ StructType *ST = cast<StructType>(VT);
+ if (ST->getNumElements() != UT->getNumElements())
+ return nullptr;
+ for (const Type *EltT : ST->elements()) {
+ if (EltT != UT->getElementType())
+ return nullptr;
+ }
+ }
+ return U;
+}
+
/// \brief Combine stores to match the type of value being stored.
///
/// The core idea here is that the memory does not have any intrinsic type and
@@ -914,6 +969,11 @@
return true;
}
+ if (Value *U = likeBitCastFromVector(IC, V)) {
+ combineStoreToNewValue(IC, SI, U);
+ return true;
+ }
+
// FIXME: We should also canonicalize loads of vectors when their elements are
// cast to other types.
return false;
Index: test/Transforms/InstCombine/insert-val-extract-elem.ll
===================================================================
--- a/test/Transforms/InstCombine/insert-val-extract-elem.ll
+++ b/test/Transforms/InstCombine/insert-val-extract-elem.ll
@@ -0,0 +1,53 @@
+; RUN: opt -S -instcombine %s | FileCheck %s
+
+; CHECK-NOT: insertvalue
+; CHECK-NOT: extractelement
+; CHECK: store <2 x double>
+define void @julia_2xdouble([2 x double]* sret, <2 x double>*) {
+top:
+ %x = load <2 x double>, <2 x double>* %1
+ %x0 = extractelement <2 x double> %x, i32 0
+ %i0 = insertvalue [2 x double] undef, double %x0, 0
+ %x1 = extractelement <2 x double> %x, i32 1
+ %i1 = insertvalue [2 x double] %i0, double %x1, 1
+ store [2 x double] %i1, [2 x double]* %0, align 4
+ ret void
+}
+
+; CHECK-NOT: insertvalue
+; CHECK-NOT: extractelement
+; CHECK: store <4 x float>
+define void @julia_4xfloat([4 x float]* sret, <4 x float>*) {
+top:
+ %x = load <4 x float>, <4 x float>* %1
+ %x0 = extractelement <4 x float> %x, i32 0
+ %i0 = insertvalue [4 x float] undef, float %x0, 0
+ %x1 = extractelement <4 x float> %x, i32 1
+ %i1 = insertvalue [4 x float] %i0, float %x1, 1
+ %x2 = extractelement <4 x float> %x, i32 2
+ %i2 = insertvalue [4 x float] %i1, float %x2, 2
+ %x3 = extractelement <4 x float> %x, i32 3
+ %i3 = insertvalue [4 x float] %i2, float %x3, 3
+ store [4 x float] %i3, [4 x float]* %0, align 4
+ ret void
+}
+
+%pseudovec = type { float, float, float, float }
+
+; CHECK-NOT: insertvalue
+; CHECK-NOT: extractelement
+; CHECK: store <4 x float>
+define void @julia_pseudovec(%pseudovec* sret, <4 x float>*) {
+top:
+ %x = load <4 x float>, <4 x float>* %1
+ %x0 = extractelement <4 x float> %x, i32 0
+ %i0 = insertvalue %pseudovec undef, float %x0, 0
+ %x1 = extractelement <4 x float> %x, i32 1
+ %i1 = insertvalue %pseudovec %i0, float %x1, 1
+ %x2 = extractelement <4 x float> %x, i32 2
+ %i2 = insertvalue %pseudovec %i1, float %x2, 2
+ %x3 = extractelement <4 x float> %x, i32 3
+ %i3 = insertvalue %pseudovec %i2, float %x3, 3
+ store %pseudovec %i3, %pseudovec* %0, align 4
+ ret void
+}