1 ; RUN: llc < %s -asm-verbose=false -verify-machineinstrs | FileCheck %s 2 3 ; Test the register stackifier pass. 4 5 target datalayout = "e-p:32:32-i64:64-n32:64-S128" 6 target triple = "wasm32-unknown-unknown" 7 8 ; No because of pointer aliasing. 9 10 ; CHECK-LABEL: no0: 11 ; CHECK: return $1{{$}} 12 define i32 @no0(i32* %p, i32* %q) { 13 %t = load i32, i32* %q 14 store i32 0, i32* %p 15 ret i32 %t 16 } 17 18 ; No because of side effects. 19 20 ; CHECK-LABEL: no1: 21 ; CHECK: return $1{{$}} 22 define i32 @no1(i32* %p, i32* dereferenceable(4) %q) { 23 %t = load volatile i32, i32* %q, !invariant.load !0 24 store volatile i32 0, i32* %p 25 ret i32 %t 26 } 27 28 ; Yes because of invariant load and no side effects. 29 30 ; CHECK-LABEL: yes0: 31 ; CHECK: return $pop0{{$}} 32 define i32 @yes0(i32* %p, i32* dereferenceable(4) %q) { 33 %t = load i32, i32* %q, !invariant.load !0 34 store i32 0, i32* %p 35 ret i32 %t 36 } 37 38 ; Yes because of no intervening side effects. 39 40 ; CHECK-LABEL: yes1: 41 ; CHECK: return $pop0{{$}} 42 define i32 @yes1(i32* %q) { 43 %t = load volatile i32, i32* %q 44 ret i32 %t 45 } 46 47 ; Don't schedule stack uses into the stack. To reduce register pressure, the 48 ; scheduler might be tempted to move the definition of $2 down. However, this 49 ; would risk getting incorrect liveness if the instructions are later 50 ; rearranged to make the stack contiguous. 51 52 ; CHECK-LABEL: stack_uses: 53 ; CHECK-NEXT: .param i32, i32, i32, i32{{$}} 54 ; CHECK-NEXT: .result i32{{$}} 55 ; CHECK-NEXT: .local i32, i32{{$}} 56 ; CHECK-NEXT: i32.const $4=, 1{{$}} 57 ; CHECK-NEXT: i32.const $5=, 2{{$}} 58 ; CHECK-NEXT: i32.lt_s $push0=, $0, $4{{$}} 59 ; CHECK-NEXT: i32.lt_s $push1=, $1, $5{{$}} 60 ; CHECK-NEXT: i32.xor $push4=, $pop0, $pop1{{$}} 61 ; CHECK-NEXT: i32.lt_s $push2=, $2, $4{{$}} 62 ; CHECK-NEXT: i32.lt_s $push3=, $3, $5{{$}} 63 ; CHECK-NEXT: i32.xor $push5=, $pop2, $pop3{{$}} 64 ; CHECK-NEXT: i32.xor $push6=, $pop4, $pop5{{$}} 65 ; CHECK-NEXT: i32.ne $push7=, $pop6, $4{{$}} 66 ; CHECK-NEXT: block BB4_2{{$}} 67 ; CHECK-NEXT: br_if $pop7, BB4_2{{$}} 68 ; CHECK-NEXT: i32.const $push8=, 0{{$}} 69 ; CHECK-NEXT: return $pop8{{$}} 70 ; CHECK-NEXT: BB4_2: 71 ; CHECK-NEXT: return $4{{$}} 72 define i32 @stack_uses(i32 %x, i32 %y, i32 %z, i32 %w) { 73 entry: 74 %c = icmp sle i32 %x, 0 75 %d = icmp sle i32 %y, 1 76 %e = icmp sle i32 %z, 0 77 %f = icmp sle i32 %w, 1 78 %g = xor i1 %c, %d 79 %h = xor i1 %e, %f 80 %i = xor i1 %g, %h 81 br i1 %i, label %true, label %false 82 true: 83 ret i32 0 84 false: 85 ret i32 1 86 } 87 88 !0 = !{} 89
