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1; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
2; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=bdver1 | FileCheck %s
3
4; Verify that for the architectures that are known to have poor latency
5; double precision shift instructions we generate alternative sequence
6; of instructions with lower latencies instead of shld instruction.
7
8;uint64_t lshift1(uint64_t a, uint64_t b)
9;{
10;    return (a << 1) | (b >> 63);
11;}
12
13define i64 @lshift1(i64 %a, i64 %b) nounwind readnone uwtable {
14; CHECK-LABEL: lshift1:
15; CHECK:       # %bb.0: # %entry
16; CHECK-NEXT:    shrq $63, %rsi
17; CHECK-NEXT:    leaq (%rsi,%rdi,2), %rax
18; CHECK-NEXT:    retq
19entry:
20  %shl = shl i64 %a, 1
21  %shr = lshr i64 %b, 63
22  %or = or i64 %shr, %shl
23  ret i64 %or
24}
25
26;uint64_t lshift2(uint64_t a, uint64_t b)
27;{
28;    return (a << 2) | (b >> 62);
29;}
30
31define i64 @lshift2(i64 %a, i64 %b) nounwind readnone uwtable {
32; CHECK-LABEL: lshift2:
33; CHECK:       # %bb.0: # %entry
34; CHECK-NEXT:    shrq $62, %rsi
35; CHECK-NEXT:    leaq (%rsi,%rdi,4), %rax
36; CHECK-NEXT:    retq
37entry:
38  %shl = shl i64 %a, 2
39  %shr = lshr i64 %b, 62
40  %or = or i64 %shr, %shl
41  ret i64 %or
42}
43
44;uint64_t lshift7(uint64_t a, uint64_t b)
45;{
46;    return (a << 7) | (b >> 57);
47;}
48
49define i64 @lshift7(i64 %a, i64 %b) nounwind readnone uwtable {
50; CHECK-LABEL: lshift7:
51; CHECK:       # %bb.0: # %entry
52; CHECK-NEXT:    shrq $57, %rsi
53; CHECK-NEXT:    shlq $7, %rdi
54; CHECK-NEXT:    leaq (%rdi,%rsi), %rax
55; CHECK-NEXT:    retq
56entry:
57  %shl = shl i64 %a, 7
58  %shr = lshr i64 %b, 57
59  %or = or i64 %shr, %shl
60  ret i64 %or
61}
62
63;uint64_t lshift63(uint64_t a, uint64_t b)
64;{
65;    return (a << 63) | (b >> 1);
66;}
67
68define i64 @lshift63(i64 %a, i64 %b) nounwind readnone uwtable {
69; CHECK-LABEL: lshift63:
70; CHECK:       # %bb.0: # %entry
71; CHECK-NEXT:    shrq %rsi
72; CHECK-NEXT:    shlq $63, %rdi
73; CHECK-NEXT:    leaq (%rdi,%rsi), %rax
74; CHECK-NEXT:    retq
75entry:
76  %shl = shl i64 %a, 63
77  %shr = lshr i64 %b, 1
78  %or = or i64 %shr, %shl
79  ret i64 %or
80}
81