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|
; RUN: opt < %s -slsr -gvn -dce -S | FileCheck %s
target datalayout = "e-i64:64-v16:16-v32:32-n16:32:64"
define void @slsr1(i32 %b, i32 %s) {
; CHECK-LABEL: @slsr1(
; foo(b * s);
%mul0 = mul i32 %b, %s
; CHECK: mul i32
; CHECK-NOT: mul i32
call void @foo(i32 %mul0)
; foo((b + 1) * s);
%b1 = add i32 %b, 1
%mul1 = mul i32 %b1, %s
call void @foo(i32 %mul1)
; foo((b + 2) * s);
%b2 = add i32 %b, 2
%mul2 = mul i32 %b2, %s
call void @foo(i32 %mul2)
ret void
}
; foo(a * b)
; foo((a + 1) * b)
; foo(a * (b + 1))
; foo((a + 1) * (b + 1))
define void @slsr2(i32 %a, i32 %b) {
; CHECK-LABEL: @slsr2(
%a1 = add i32 %a, 1
%b1 = add i32 %b, 1
%mul0 = mul i32 %a, %b
; CHECK: mul i32
; CHECK-NOT: mul i32
%mul1 = mul i32 %a1, %b
%mul2 = mul i32 %a, %b1
%mul3 = mul i32 %a1, %b1
call void @foo(i32 %mul0)
call void @foo(i32 %mul1)
call void @foo(i32 %mul2)
call void @foo(i32 %mul3)
ret void
}
; The bump is a multiple of the stride.
;
; foo(b * s);
; foo((b + 2) * s);
; foo((b + 4) * s);
; =>
; mul0 = b * s;
; bump = s * 2;
; mul1 = mul0 + bump; // GVN ensures mul1 and mul2 use the same bump.
; mul2 = mul1 + bump;
define void @slsr3(i32 %b, i32 %s) {
; CHECK-LABEL: @slsr3(
%mul0 = mul i32 %b, %s
; CHECK: mul i32
call void @foo(i32 %mul0)
%b1 = add i32 %b, 2
%mul1 = mul i32 %b1, %s
; CHECK: [[BUMP:%[a-zA-Z0-9]+]] = shl i32 %s, 1
; CHECK: %mul1 = add i32 %mul0, [[BUMP]]
call void @foo(i32 %mul1)
%b2 = add i32 %b, 4
%mul2 = mul i32 %b2, %s
; CHECK: %mul2 = add i32 %mul1, [[BUMP]]
call void @foo(i32 %mul2)
ret void
}
; Do not rewrite a candidate if its potential basis does not dominate it.
;
; if (cond)
; foo(a * b);
; foo((a + 1) * b);
define void @not_dominate(i1 %cond, i32 %a, i32 %b) {
; CHECK-LABEL: @not_dominate(
entry:
%a1 = add i32 %a, 1
br i1 %cond, label %then, label %merge
then:
%mul0 = mul i32 %a, %b
; CHECK: %mul0 = mul i32 %a, %b
call void @foo(i32 %mul0)
br label %merge
merge:
%mul1 = mul i32 %a1, %b
; CHECK: %mul1 = mul i32 %a1, %b
call void @foo(i32 %mul1)
ret void
}
declare void @foo(i32)
|
