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; RUN: opt -consthoist -S < %s | FileCheck %s
target triple = "thumbv6m-none-eabi"
; Allocas in the entry block get handled (for free) by
; prologue/epilogue. Elsewhere they're fair game though.
define void @avoid_allocas() {
; CHECK-LABEL: @avoid_allocas
; CHECK: %addr1 = alloca i8, i32 1000
; CHECK: %addr2 = alloca i8, i32 1020
%addr1 = alloca i8, i32 1000
%addr2 = alloca i8, i32 1020
br label %elsewhere
elsewhere:
; CHECK: [[BASE:%.*]] = bitcast i32 1000 to i32
; CHECK: alloca i8, i32 [[BASE]]
; CHECK: [[NEXT:%.*]] = add i32 [[BASE]], 20
; CHECK: alloca i8, i32 [[NEXT]]
%addr3 = alloca i8, i32 1000
%addr4 = alloca i8, i32 1020
ret void
}
; The case values of switch instructions are required to be constants.
define void @avoid_switch(i32 %in) {
; CHECK-LABEL: @avoid_switch
; CHECK: switch i32 %in, label %default [
; CHECK: i32 1000, label %bb1
; CHECK: i32 1020, label %bb2
; CHECK: ]
switch i32 %in, label %default
[ i32 1000, label %bb1
i32 1020, label %bb2 ]
bb1:
ret void
bb2:
ret void
default:
ret void
}
; We don't want to convert constant divides because the benefit from converting
; them to a mul in the backend is larget than constant materialization savings.
define void @signed_const_division(i32 %in1, i32 %in2, i32* %addr) {
; CHECK-LABEL: @signed_const_division
; CHECK: %res1 = sdiv i32 %l1, 1000000000
; CHECK: %res2 = srem i32 %l2, 1000000000
entry:
br label %loop
loop:
%l1 = phi i32 [%res1, %loop], [%in1, %entry]
%l2 = phi i32 [%res2, %loop], [%in2, %entry]
%res1 = sdiv i32 %l1, 1000000000
store volatile i32 %res1, i32* %addr
%res2 = srem i32 %l2, 1000000000
store volatile i32 %res2, i32* %addr
%again = icmp eq i32 %res1, %res2
br i1 %again, label %loop, label %end
end:
ret void
}
define void @unsigned_const_division(i32 %in1, i32 %in2, i32* %addr) {
; CHECK-LABEL: @unsigned_const_division
; CHECK: %res1 = udiv i32 %l1, 1000000000
; CHECK: %res2 = urem i32 %l2, 1000000000
entry:
br label %loop
loop:
%l1 = phi i32 [%res1, %loop], [%in1, %entry]
%l2 = phi i32 [%res2, %loop], [%in2, %entry]
%res1 = udiv i32 %l1, 1000000000
store volatile i32 %res1, i32* %addr
%res2 = urem i32 %l2, 1000000000
store volatile i32 %res2, i32* %addr
%again = icmp eq i32 %res1, %res2
br i1 %again, label %loop, label %end
end:
ret void
}
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