cmd/compile: use correct type in riscv64 late lower pass

The right-hand side SLLI always contains valid content in the high 32 bits,
so we should use the 64 bit integer type. Using wrong type may lead to wrong
optimizations in cse pass.

Should fix x/text test failures.

Change-Id: I972dd913b8fb238d180bb12f8b1801adc8503fc0
Reviewed-on: https://go-review.googlesource.com/c/go/+/443875
Reviewed-by: Dmitri Goutnik <[email protected]>
Reviewed-by: Cherry Mui <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Run-TryBot: Wayne Zuo <[email protected]>
Reviewed-by: David Chase <[email protected]>

Author: wdvxdr1123

src/cmd/compile/internal/ssa/_gen/RISCV64latelower.rules

@@ -3,15 +3,15 @@
 // license that can be found in the LICENSE file.
 
 // Fold constant shift with extension.
-(SRAI <t> [c] (MOVBreg  x)) && c <   8 => (SRAI [56+c] (SLLI <t> [56] x))
-(SRAI <t> [c] (MOVHreg  x)) && c <  16 => (SRAI [48+c] (SLLI <t> [48] x))
-(SRAI <t> [c] (MOVWreg  x)) && c <  32 => (SRAI [32+c] (SLLI <t> [32] x))
-(SRLI <t> [c] (MOVBUreg x)) && c <   8 => (SRLI [56+c] (SLLI <t> [56] x))
-(SRLI <t> [c] (MOVHUreg x)) && c <  16 => (SRLI [48+c] (SLLI <t> [48] x))
-(SRLI <t> [c] (MOVWUreg x)) && c <  32 => (SRLI [32+c] (SLLI <t> [32] x))
-(SLLI <t> [c] (MOVBUreg x)) && c <= 56 => (SRLI [56-c] (SLLI <t> [56] x))
-(SLLI <t> [c] (MOVHUreg x)) && c <= 48 => (SRLI [48-c] (SLLI <t> [48] x))
-(SLLI <t> [c] (MOVWUreg x)) && c <= 32 => (SRLI [32-c] (SLLI <t> [32] x))
+(SRAI [c] (MOVBreg  x)) && c <   8 => (SRAI [56+c] (SLLI <typ.Int64> [56] x))
+(SRAI [c] (MOVHreg  x)) && c <  16 => (SRAI [48+c] (SLLI <typ.Int64> [48] x))
+(SRAI [c] (MOVWreg  x)) && c <  32 => (SRAI [32+c] (SLLI <typ.Int64> [32] x))
+(SRLI [c] (MOVBUreg x)) && c <   8 => (SRLI [56+c] (SLLI <typ.UInt64> [56] x))
+(SRLI [c] (MOVHUreg x)) && c <  16 => (SRLI [48+c] (SLLI <typ.UInt64> [48] x))
+(SRLI [c] (MOVWUreg x)) && c <  32 => (SRLI [32+c] (SLLI <typ.UInt64> [32] x))
+(SLLI [c] (MOVBUreg x)) && c <= 56 => (SRLI [56-c] (SLLI <typ.UInt64> [56] x))
+(SLLI [c] (MOVHUreg x)) && c <= 48 => (SRLI [48-c] (SLLI <typ.UInt64> [48] x))
+(SLLI [c] (MOVWUreg x)) && c <= 32 => (SRLI [32-c] (SLLI <typ.UInt64> [32] x))
 
 // Shift by zero.
 (SRAI [0] x) => x