riscv64: Fix ctz edge case

Author: afonso360

cranelift/codegen/src/isa/riscv64/inst.isle

@@ -971,7 +971,7 @@
 (rule 1 (lower_ctz (fits_in_16 ty) x)
   (if-let $true (has_zbb))
   (let ((tmp Reg (bseti x (ty_bits ty))))
-    (alu_rr_funct12 (AluOPRRI.Ctzw) x)))
+    (alu_rr_funct12 (AluOPRRI.Ctzw) tmp)))
 
 (rule 2 (lower_ctz $I32 x)
   (if-let $true (has_zbb))

cranelift/filetests/filetests/isa/riscv64/ctz-zbb-zbs.clif

@@ -11,13 +11,13 @@ block0(v0: i8):
 ; VCode:
 ; block0:
 ;   bseti t2,a0,8
-;   ctzw a0,a0
+;   ctzw a0,t2
 ;   ret
 ; 
 ; Disassembled:
 ; block0: ; offset 0x0
 ;   .byte 0x93, 0x13, 0x85, 0x28
-;   .byte 0x1b, 0x15, 0x15, 0x60
+;   .byte 0x1b, 0x95, 0x13, 0x60
 ;   ret
 
 function %ctz_i16(i16) -> i16 {
@@ -29,13 +29,13 @@ block0(v0: i16):
 ; VCode:
 ; block0:
 ;   bseti t2,a0,16
-;   ctzw a0,a0
+;   ctzw a0,t2
 ;   ret
 ; 
 ; Disassembled:
 ; block0: ; offset 0x0
 ;   .byte 0x93, 0x13, 0x05, 0x29
-;   .byte 0x1b, 0x15, 0x15, 0x60
+;   .byte 0x1b, 0x95, 0x13, 0x60
 ;   ret
 
 function %ctz_i32(i32) -> i32 {

cranelift/filetests/filetests/isa/riscv64/ctz-zbb.clif

@@ -12,13 +12,13 @@ block0(v0: i8):
 ; VCode:
 ; block0:
 ;   ori t2,a0,256
-;   ctzw a0,a0
+;   ctzw a0,t2
 ;   ret
 ; 
 ; Disassembled:
 ; block0: ; offset 0x0
 ;   ori t2, a0, 0x100
-;   .byte 0x1b, 0x15, 0x15, 0x60
+;   .byte 0x1b, 0x95, 0x13, 0x60
 ;   ret
 
 function %ctz_i16(i16) -> i16 {
@@ -31,14 +31,14 @@ block0(v0: i16):
 ; block0:
 ;   lui t2,16
 ;   or a1,a0,t2
-;   ctzw a0,a0
+;   ctzw a0,a1
 ;   ret
 ; 
 ; Disassembled:
 ; block0: ; offset 0x0
 ;   lui t2, 0x10
 ;   or a1, a0, t2
-;   .byte 0x1b, 0x15, 0x15, 0x60
+;   .byte 0x1b, 0x95, 0x15, 0x60
 ;   ret
 
 function %ctz_i32(i32) -> i32 {

cranelift/filetests/filetests/runtests/clz.clif

@@ -12,6 +12,7 @@ block0(v0: i8):
     v1 = clz v0
     return v1
 }
+; run: %clz_i8(0) == 8
 ; run: %clz_i8(1) == 7
 ; run: %clz_i8(0x40) == 1
 ; run: %clz_i8(-1) == 0
@@ -21,6 +22,7 @@ block0(v0: i16):
     v1 = clz v0
     return v1
 }
+; run: %clz_i16(0) == 16
 ; run: %clz_i16(1) == 15
 ; run: %clz_i16(0x4000) == 1
 ; run: %clz_i16(-1) == 0
@@ -30,6 +32,7 @@ block0(v0: i32):
     v1 = clz v0
     return v1
 }
+; run: %clz_i32(0) == 32
 ; run: %clz_i32(1) == 31
 ; run: %clz_i32(0x40000000) == 1
 ; run: %clz_i32(-1) == 0
@@ -39,6 +42,7 @@ block0(v0: i64):
     v1 = clz v0
     return v1
 }
+; run: %clz_i64(0) == 64
 ; run: %clz_i64(1) == 63
 ; run: %clz_i64(0x4000000000000000) == 1
 ; run: %clz_i64(-1) == 0

cranelift/filetests/filetests/runtests/ctz.clif

@@ -13,6 +13,7 @@ block0(v0: i8):
     v1 = ctz v0
     return v1
 }
+; run: %ctz_i8(0) == 8
 ; run: %ctz_i8(1) == 0
 ; run: %ctz_i8(0x40) == 6
 ; run: %ctz_i8(-1) == 0
@@ -22,6 +23,7 @@ block0(v0: i16):
     v1 = ctz v0
     return v1
 }
+; run: %ctz_i16(0) == 16
 ; run: %ctz_i16(1) == 0
 ; run: %ctz_i16(0x4000) == 14
 ; run: %ctz_i16(-1) == 0
@@ -31,6 +33,7 @@ block0(v0: i32):
     v1 = ctz v0
     return v1
 }
+; run: %ctz_i32(0) == 32
 ; run: %ctz_i32(1) == 0
 ; run: %ctz_i32(0x40000000) == 30
 ; run: %ctz_i32(-1) == 0
@@ -40,6 +43,7 @@ block0(v0: i64):
     v1 = ctz v0
     return v1
 }
+; run: %ctz_i64(0) == 64
 ; run: %ctz_i64(1) == 0
 ; run: %ctz_i64(0x4000000000000000) == 62
 ; run: %ctz_i64(-1) == 0