1;Check 5.5 Parameter Passing --> Stage C --> C.4 statement, when NSAA is not
2;equal to SP.
3;
4; Our purpose: make NSAA != SP, and only after start to use GPRs.
5;
6;Co-Processor register candidates may be either in VFP or in stack, so after
7;all VFP are allocated, stack is used. We can use stack without GPR allocation
8;in that case, passing 9 f64 params, for example.
9;First eight params goes to d0-d7, ninth one goes to the stack.
10;Now, as 10th parameter, we pass i32, and it must go to R0.
11;
12;5.5 Parameter Passing, Stage C:
13;
14;C.2.cp If the argument is a CPRC then any co-processor registers in that class
15;that are unallocated are marked as unavailable. The NSAA is adjusted upwards
16;until it is correctly aligned for the argument and the argument is copied to
17;the memory at the adjusted NSAA. The NSAA is further incremented by the size
18;of the argument. The argument has now been allocated.
19;...
20;C.4 If the size in words of the argument is not more than r4 minus NCRN, the
21;argument is copied into core registers, starting at the NCRN. The NCRN is
22;incremented by the number of registers used. Successive registers hold the
23;parts of the argument they would hold if its value were loaded into those
24;registers from memory using an LDM instruction. The argument has now been
25;allocated.
26;
27;What is actually checked here:
28;Here we check that i32 param goes to r0.
29;
30;Current test-case was produced with command:
31;arm-linux-gnueabihf-clang -mcpu=cortex-a9 params-to-GPR.c -S -O1 -emit-llvm
32;
33;// params-to-GRP.c:
34;
35;void fooUseI32(unsigned);
36;
37;void foo(long double p0,
38;         long double p1,
39;         long double p2,
40;         long double p3,
41;         long double p4,
42;         long double p5,
43;         long double p6,
44;         long double p7,
45;         long double p8,
46;         unsigned p9) {
47;  fooUseI32(p9);
48;}
49;
50;void doFoo() {
51;  foo( 1,2,3,4,5,6,7,8,9, 43 );
52;}
53
54;RUN: llc -mtriple=thumbv7-linux-gnueabihf -float-abi=hard < %s | FileCheck %s
55;
56;CHECK-LABEL:     foo:
57;CHECK-NOT:     mov r0
58;CHECK-NOT:     ldr r0
59;CHECK:         bl fooUseI32
60;CHECK-LABEL:     doFoo:
61;CHECK:         movs    r0, #43
62;CHECK:         bl      foo
63
64define void @foo(double %p0, ; --> D0
65                 double %p1, ; --> D1
66		 double %p2, ; --> D2
67		 double %p3, ; --> D3
68		 double %p4, ; --> D4
69		 double %p5, ; --> D5
70		 double %p6, ; --> D6
71		 double %p7, ; --> D7
72		 double %p8, ; --> Stack
73		 i32 %p9) #0 { ; --> R0, not Stack+8
74entry:
75  call void @fooUseI32(i32 %p9)
76  ret void
77}
78
79declare void @fooUseI32(i32)
80
81define void @doFoo() {
82entry:
83  tail call void @foo(double 23.0, ; --> D0
84                      double 23.1, ; --> D1
85		      double 23.2, ; --> D2
86                      double 23.3, ; --> D3
87                      double 23.4, ; --> D4
88                      double 23.5, ; --> D5
89                      double 23.6, ; --> D6
90                      double 23.7, ; --> D7
91                      double 23.8, ; --> Stack
92                      i32 43)      ; --> R0, not Stack+8
93  ret void
94}
95
96