llvm-project/llvm/test/CodeGen/ARM/avoid-cpsr-rmw.ll

51 lines
1.7 KiB
LLVM

; RUN: llc < %s -mtriple=thumbv7-apple-darwin -mcpu=cortex-a9 | FileCheck %s
; Avoid some 's' 16-bit instruction which partially update CPSR (and add false
; dependency) when it isn't dependent on last CPSR defining instruction.
; rdar://8928208
define i32 @t1(i32 %a, i32 %b, i32 %c, i32 %d) nounwind readnone {
entry:
; CHECK: t1:
; CHECK: muls [[REG:(r[0-9]+)]], r2, r3
; CHECK-NEXT: mul [[REG2:(r[0-9]+)]], r0, r1
; CHECK-NEXT: muls r0, [[REG2]], [[REG]]
%0 = mul nsw i32 %a, %b
%1 = mul nsw i32 %c, %d
%2 = mul nsw i32 %0, %1
ret i32 %2
}
; Avoid partial CPSR dependency via loop backedge.
; rdar://10357570
define void @t2(i32* nocapture %ptr1, i32* %ptr2, i32 %c) nounwind {
entry:
; CHECK: t2:
%tobool7 = icmp eq i32* %ptr2, null
br i1 %tobool7, label %while.end, label %while.body
while.body:
; CHECK: while.body
; CHECK: mul r{{[0-9]+}}
; CHECK-NOT: muls
%ptr1.addr.09 = phi i32* [ %add.ptr, %while.body ], [ %ptr1, %entry ]
%ptr2.addr.08 = phi i32* [ %incdec.ptr, %while.body ], [ %ptr2, %entry ]
%0 = load i32* %ptr1.addr.09, align 4
%arrayidx1 = getelementptr inbounds i32* %ptr1.addr.09, i32 1
%1 = load i32* %arrayidx1, align 4
%arrayidx3 = getelementptr inbounds i32* %ptr1.addr.09, i32 2
%2 = load i32* %arrayidx3, align 4
%arrayidx4 = getelementptr inbounds i32* %ptr1.addr.09, i32 3
%3 = load i32* %arrayidx4, align 4
%add.ptr = getelementptr inbounds i32* %ptr1.addr.09, i32 4
%mul = mul i32 %1, %0
%mul5 = mul i32 %mul, %2
%mul6 = mul i32 %mul5, %3
store i32 %mul6, i32* %ptr2.addr.08, align 4
%incdec.ptr = getelementptr inbounds i32* %ptr2.addr.08, i32 -1
%tobool = icmp eq i32* %incdec.ptr, null
br i1 %tobool, label %while.end, label %while.body
while.end:
ret void
}