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 64 define 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 74 entry: 75 call void @fooUseI32(i32 %p9) 76 ret void 77 } 78 79 declare void @fooUseI32(i32) 80 81 define void @doFoo() { 82 entry: 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
