mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-15 04:30:12 +00:00
80a3301b37
...into (ashr (shl (anyext X), ...), ...), which requires one fewer instruction. The (anyext X) can sometimes be simplified too. I didn't do this in DAGCombiner because widening shifts isn't a win on all targets. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199114 91177308-0d34-0410-b5e6-96231b3b80d8
92 lines
2.1 KiB
LLVM
92 lines
2.1 KiB
LLVM
; Test compound shifts.
|
|
;
|
|
; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
|
|
|
|
; Test a shift right followed by a sign extension. This can use two shifts.
|
|
define i64 @f1(i32 %a) {
|
|
; CHECK-LABEL: f1:
|
|
; CHECK: sllg [[REG:%r[0-5]]], %r2, 62
|
|
; CHECK: srag %r2, [[REG]], 63
|
|
; CHECK: br %r14
|
|
%shr = lshr i32 %a, 1
|
|
%trunc = trunc i32 %shr to i1
|
|
%ext = sext i1 %trunc to i64
|
|
ret i64 %ext
|
|
}
|
|
|
|
; ...and again with the highest shift count that doesn't reduce to an
|
|
; ashr/sext pair.
|
|
define i64 @f2(i32 %a) {
|
|
; CHECK-LABEL: f2:
|
|
; CHECK: sllg [[REG:%r[0-5]]], %r2, 33
|
|
; CHECK: srag %r2, [[REG]], 63
|
|
; CHECK: br %r14
|
|
%shr = lshr i32 %a, 30
|
|
%trunc = trunc i32 %shr to i1
|
|
%ext = sext i1 %trunc to i64
|
|
ret i64 %ext
|
|
}
|
|
|
|
; Test a left shift that of an extended right shift in a case where folding
|
|
; is possible.
|
|
define i64 @f3(i32 %a) {
|
|
; CHECK-LABEL: f3:
|
|
; CHECK: risbg %r2, %r2, 27, 181, 9
|
|
; CHECK: br %r14
|
|
%shr = lshr i32 %a, 1
|
|
%ext = zext i32 %shr to i64
|
|
%shl = shl i64 %ext, 10
|
|
%and = and i64 %shl, 137438952960
|
|
ret i64 %and
|
|
}
|
|
|
|
; ...and again with a larger right shift.
|
|
define i64 @f4(i32 %a) {
|
|
; CHECK-LABEL: f4:
|
|
; CHECK: risbg %r2, %r2, 30, 158, 3
|
|
; CHECK: br %r14
|
|
%shr = lshr i32 %a, 30
|
|
%ext = sext i32 %shr to i64
|
|
%shl = shl i64 %ext, 33
|
|
%and = and i64 %shl, 8589934592
|
|
ret i64 %and
|
|
}
|
|
|
|
; Repeat the previous test in a case where all bits outside the
|
|
; bottom 3 matter.
|
|
define i64 @f5(i32 %a) {
|
|
; CHECK-LABEL: f5:
|
|
; CHECK: risbg %r2, %r2, 29, 158, 3
|
|
; CHECK: lhi %r2, 7
|
|
; CHECK: br %r14
|
|
%shr = lshr i32 %a, 30
|
|
%ext = sext i32 %shr to i64
|
|
%shl = shl i64 %ext, 33
|
|
%or = or i64 %shl, 7
|
|
ret i64 %or
|
|
}
|
|
|
|
; Test that SRA gets replaced with SRL if the sign bit is the only one
|
|
; that matters.
|
|
define i64 @f6(i64 %a) {
|
|
; CHECK-LABEL: f6:
|
|
; CHECK: risbg %r2, %r2, 55, 183, 19
|
|
; CHECK: br %r14
|
|
%shl = shl i64 %a, 10
|
|
%shr = ashr i64 %shl, 60
|
|
%and = and i64 %shr, 256
|
|
ret i64 %and
|
|
}
|
|
|
|
; Test another form of f1.
|
|
define i64 @f7(i32 %a) {
|
|
; CHECK-LABEL: f7:
|
|
; CHECK: sllg [[REG:%r[0-5]]], %r2, 62
|
|
; CHECK: srag %r2, [[REG]], 63
|
|
; CHECK: br %r14
|
|
%1 = shl i32 %a, 30
|
|
%sext = ashr i32 %1, 31
|
|
%ext = sext i32 %sext to i64
|
|
ret i64 %ext
|
|
}
|