| ; RUN: llc -mtriple=hexagon < %s | FileCheck %s |
| |
| ; Verify that SelectSHL handles (shl (mul val, const), const) with negative |
| ; multiply constants. The left shift of the negative constant must be done in |
| ; unsigned arithmetic to avoid undefined behavior. |
| |
| ; The multiply constant 0xAAAAAAAB shifted left by 1 does not fit in a signed |
| ; 9-bit immediate, so this should not be folded into M2_mpysmi. |
| define i32 @shl_mul_neg_large(i32 %x) #0 { |
| ; CHECK-LABEL: shl_mul_neg_large: |
| ; CHECK: +mpyi(r0,##1431655766) |
| ; CHECK: jumpr r31 |
| entry: |
| %m = mul i32 %x, u0xAAAAAAAB |
| %s = shl i32 %m, 1 |
| ret i32 %s |
| } |
| |
| ; A small negative multiply constant (-3) shifted left by 1 gives -6, which |
| ; fits in a signed 9-bit immediate. This should be folded into M2_mpysmi. |
| define i32 @shl_mul_neg_small(i32 %x) #0 { |
| ; CHECK-LABEL: shl_mul_neg_small: |
| ; CHECK: -mpyi(r0,#6) |
| ; CHECK: jumpr r31 |
| entry: |
| %m = mul i32 %x, -3 |
| %s = shl i32 %m, 1 |
| ret i32 %s |
| } |
| |
| attributes #0 = { nounwind "target-cpu"="hexagonv60" } |
