llvm-6502/test/CodeGen/AArch64/mul_pow2.ll
Chad Rosier f1de1adc82 [AArch64] When combining constant mul of -3, prefer (sub x, (shl x, N)).
This change only effects codegen when the constant is -3.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231085 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-03 17:31:01 +00:00

123 lines
2.0 KiB
LLVM

; RUN: llc < %s -march=aarch64 | FileCheck %s
; Convert mul x, pow2 to shift.
; Convert mul x, pow2 +/- 1 to shift + add/sub.
define i32 @test2(i32 %x) {
; CHECK-LABEL: test2
; CHECK: lsl w0, w0, #1
%mul = shl nsw i32 %x, 1
ret i32 %mul
}
define i32 @test3(i32 %x) {
; CHECK-LABEL: test3
; CHECK: add w0, w0, w0, lsl #1
%mul = mul nsw i32 %x, 3
ret i32 %mul
}
define i32 @test4(i32 %x) {
; CHECK-LABEL: test4
; CHECK: lsl w0, w0, #2
%mul = shl nsw i32 %x, 2
ret i32 %mul
}
define i32 @test5(i32 %x) {
; CHECK-LABEL: test5
; CHECK: add w0, w0, w0, lsl #2
%mul = mul nsw i32 %x, 5
ret i32 %mul
}
define i32 @test7(i32 %x) {
; CHECK-LABEL: test7
; CHECK: lsl {{w[0-9]+}}, w0, #3
; CHECK: sub w0, {{w[0-9]+}}, w0
%mul = mul nsw i32 %x, 7
ret i32 %mul
}
define i32 @test8(i32 %x) {
; CHECK-LABEL: test8
; CHECK: lsl w0, w0, #3
%mul = shl nsw i32 %x, 3
ret i32 %mul
}
define i32 @test9(i32 %x) {
; CHECK-LABEL: test9
; CHECK: add w0, w0, w0, lsl #3
%mul = mul nsw i32 %x, 9
ret i32 %mul
}
; Convert mul x, -pow2 to shift.
; Convert mul x, -(pow2 +/- 1) to shift + add/sub.
define i32 @ntest2(i32 %x) {
; CHECK-LABEL: ntest2
; CHECK: neg w0, w0, lsl #1
%mul = mul nsw i32 %x, -2
ret i32 %mul
}
define i32 @ntest3(i32 %x) {
; CHECK-LABEL: ntest3
; CHECK: sub w0, w0, w0, lsl #2
%mul = mul nsw i32 %x, -3
ret i32 %mul
}
define i32 @ntest4(i32 %x) {
; CHECK-LABEL: ntest4
; CHECK:neg w0, w0, lsl #2
%mul = mul nsw i32 %x, -4
ret i32 %mul
}
define i32 @ntest5(i32 %x) {
; CHECK-LABEL: ntest5
; CHECK: add {{w[0-9]+}}, w0, w0, lsl #2
; CHECK: neg w0, {{w[0-9]+}}
%mul = mul nsw i32 %x, -5
ret i32 %mul
}
define i32 @ntest7(i32 %x) {
; CHECK-LABEL: ntest7
; CHECK: sub w0, w0, w0, lsl #3
%mul = mul nsw i32 %x, -7
ret i32 %mul
}
define i32 @ntest8(i32 %x) {
; CHECK-LABEL: ntest8
; CHECK: neg w0, w0, lsl #3
%mul = mul nsw i32 %x, -8
ret i32 %mul
}
define i32 @ntest9(i32 %x) {
; CHECK-LABEL: ntest9
; CHECK: add {{w[0-9]+}}, w0, w0, lsl #3
; CHECK: neg w0, {{w[0-9]+}}
%mul = mul nsw i32 %x, -9
ret i32 %mul
}