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      1 ; RUN: llc < %s -mtriple=thumbv7-apple-ios -mcpu=cortex-a8 -regalloc=fast -optimize-regalloc=0 | FileCheck %s -check-prefix=A8
      2 ; RUN: llc < %s -mtriple=thumbv7-apple-ios -mcpu=cortex-m3 -regalloc=fast -optimize-regalloc=0 | FileCheck %s -check-prefix=M3
      3 ; rdar://6949835
      4 ; RUN: llc < %s -mtriple=thumbv7-apple-ios -mcpu=cortex-a8 -regalloc=basic | FileCheck %s -check-prefix=BASIC
      5 ; RUN: llc < %s -mtriple=thumbv7-apple-ios -mcpu=cortex-a8 -regalloc=greedy | FileCheck %s -check-prefix=GREEDY
      6 
      7 ; Magic ARM pair hints works best with linearscan / fast.
      8 
      9 ; Cortex-M3 errata 602117: LDRD with base in list may result in incorrect base
     10 ; register when interrupted or faulted.
     11 
     12 @b = external global i64*
     13 
     14 define i64 @t(i64 %a) nounwind readonly {
     15 entry:
     16 ; A8: t:
     17 ; A8:   ldrd r2, r3, [r2]
     18 
     19 ; M3: t:
     20 ; M3-NOT: ldrd
     21 
     22 	%0 = load i64** @b, align 4
     23 	%1 = load i64* %0, align 4
     24 	%2 = mul i64 %1, %a
     25 	ret i64 %2
     26 }
     27 
     28 ; rdar://10435045 mixed LDRi8/LDRi12
     29 ;
     30 ; In this case, LSR generate a sequence of LDRi8/LDRi12. We should be
     31 ; able to generate an LDRD pair here, but this is highly sensitive to
     32 ; regalloc hinting. So, this doubles as a register allocation
     33 ; test. RABasic currently does a better job within the inner loop
     34 ; because of its *lack* of hinting ability. Whereas RAGreedy keeps
     35 ; R0/R1/R2 live as the three arguments, forcing the LDRD's odd
     36 ; destination into R3. We then sensibly split LDRD again rather then
     37 ; evict another live range or use callee saved regs. Sorry if the test
     38 ; is sensitive to Regalloc changes, but it is an interesting case.
     39 ;
     40 ; BASIC: @f
     41 ; BASIC: %bb
     42 ; BASIC: ldrd
     43 ; BASIC: str
     44 ; GREEDY: @f
     45 ; GREEDY: %bb
     46 ; GREEDY: ldrd
     47 ; GREEDY: str
     48 define void @f(i32* nocapture %a, i32* nocapture %b, i32 %n) nounwind {
     49 entry:
     50   %0 = add nsw i32 %n, -1                         ; <i32> [#uses=2]
     51   %1 = icmp sgt i32 %0, 0                         ; <i1> [#uses=1]
     52   br i1 %1, label %bb, label %return
     53 
     54 bb:                                               ; preds = %bb, %entry
     55   %i.03 = phi i32 [ %tmp, %bb ], [ 0, %entry ]    ; <i32> [#uses=3]
     56   %scevgep = getelementptr i32* %a, i32 %i.03     ; <i32*> [#uses=1]
     57   %scevgep4 = getelementptr i32* %b, i32 %i.03    ; <i32*> [#uses=1]
     58   %tmp = add i32 %i.03, 1                         ; <i32> [#uses=3]
     59   %scevgep5 = getelementptr i32* %a, i32 %tmp     ; <i32*> [#uses=1]
     60   %2 = load i32* %scevgep, align 4                ; <i32> [#uses=1]
     61   %3 = load i32* %scevgep5, align 4               ; <i32> [#uses=1]
     62   %4 = add nsw i32 %3, %2                         ; <i32> [#uses=1]
     63   store i32 %4, i32* %scevgep4, align 4
     64   %exitcond = icmp eq i32 %tmp, %0                ; <i1> [#uses=1]
     65   br i1 %exitcond, label %return, label %bb
     66 
     67 return:                                           ; preds = %bb, %entry
     68   ret void
     69 }
     70