ubsan: m32c: left shift of negative value
Alan Modra
amodra@gmail.com
Thu Jan 30 13:08:00 GMT 2020
More nonsense fixing "bugs" with left shifts of signed values. Yes,
the C standard does say this is undefined (and right shifts of signed
values are implementation defined BTW) but in practice there is no
problem with current machines. 1's complement is a thing of the past.
cpu/
* m32c.cpu (f-src32-rn-unprefixed-QI): Shift before inverting.
(f-src32-rn-prefixed-QI, f-dst32-rn-unprefixed-QI): Likewise.
(f-dst32-rn-prefixed-QI): Likewise.
(f-dsp-32-s32): Mask before shifting left.
(f-dsp-48-u32, f-dsp-48-s32): Likewise.
(f-bitbase32-16-s11-unprefixed): Multiply signed field rather than
shifting left.
(f-bitbase32-24-s11-prefixed, f-bitbase32-24-s19-prefixed): Likewise.
(h-gr-SI): Mask before shifting.
opcodes/
* m32c-ibld.c: Regenerate.
diff --git a/cpu/m32c.cpu b/cpu/m32c.cpu
index 1e630a4a51..48b5acdfbd 100644
--- a/cpu/m32c.cpu
+++ b/cpu/m32c.cpu
@@ -240,7 +240,7 @@
; r1l 10'b 11'b
; r1h 11'b 01'b
(df f-src32-rn-unprefixed-QI "source Rn QI for m32c" (MACH32 m32c-isa) 10 2 UINT
- ((value pc) (or USI (and (sll (inv value) 1) 2) (and (srl value 1) 1))) ; insert
+ ((value pc) (or USI (and (inv (sll value 1)) 2) (and (srl value 1) 1))) ; insert
((value pc) (or USI (and (inv (srl value 1)) 1) (and (sll value 1) 2))) ; extract
)
; QI mode gr encoding for m32c is different than for m16c. The hardware
@@ -252,7 +252,7 @@
; r1l 10'b 11'b
; r1h 11'b 01'b
(df f-src32-rn-prefixed-QI "source Rn QI for m32c" (MACH32 m32c-isa) 18 2 UINT
- ((value pc) (or USI (and (sll (inv value) 1) 2) (and (srl value 1) 1))) ; insert
+ ((value pc) (or USI (and (inv (sll value 1)) 2) (and (srl value 1) 1))) ; insert
((value pc) (or USI (and (inv (srl value 1)) 1) (and (sll value 1) 2))) ; extract
)
; HI mode gr encoding for m32c is different than for m16c. The hardware
@@ -316,11 +316,11 @@
; r1l 10'b 11'b
; r1h 11'b 01'b
(df f-dst32-rn-unprefixed-QI "destination Rn QI for m32c" (MACH32 m32c-isa) 8 2 UINT
- ((value pc) (or USI (and (sll (inv value) 1) 2) (and (srl value 1) 1))) ; insert
+ ((value pc) (or USI (and (inv (sll value 1)) 2) (and (srl value 1) 1))) ; insert
((value pc) (or USI (and (inv (srl value 1)) 1) (and (sll value 1) 2))) ; extract
)
(df f-dst32-rn-prefixed-QI "destination Rn QI for m32c" (MACH32 m32c-isa) 16 2 UINT
- ((value pc) (or USI (and (sll (inv value) 1) 2) (and (srl value 1) 1))) ; insert
+ ((value pc) (or USI (and (inv (sll value 1)) 2) (and (srl value 1) 1))) ; insert
((value pc) (or USI (and (inv (srl value 1)) 1) (and (sll value 1) 2))) ; extract
)
; HI mode gr encoding for m32c is different than for m16c. The hardware
@@ -720,22 +720,22 @@
(ext INT
(or SI
(or SI
- (and (srl value 24) #x000000ff)
- (and (srl value 8) #x0000ff00))
+ (and (srl value 24) #x00ff)
+ (and (srl value 8) #xff00))
(or SI
- (and (sll value 8) #x00ff0000)
- (and (sll value 24) #xff000000)))))
+ (sll (and value #xff00) 8)
+ (sll (and value #x00ff) 24)))))
;; extract
((value pc)
(ext INT
(or SI
(or SI
- (and (srl value 24) #x000000ff)
- (and (srl value 8) #x0000ff00))
+ (and (srl value 24) #x00ff)
+ (and (srl value 8) #xff00))
(or SI
- (and (sll value 8) #x00ff0000)
- (and (sll value 24) #xff000000)))))
+ (sll (and value #xff00) 8)
+ (sll (and value #x00ff) 24)))))
)
(dnmf f-dsp-48-u32 "32 bit unsigned" (all-isas) UINT
@@ -746,7 +746,7 @@
)
(sequence () ; extract
(set (ifield f-dsp-48-u32) (or (and (ifield f-dsp-48-u16) #xffff)
- (and (sll (ifield f-dsp-64-u16) 16) #xffff0000)))
+ (sll (and (ifield f-dsp-64-u16) #xffff) 16)))
)
)
@@ -758,7 +758,7 @@
)
(sequence () ; extract
(set (ifield f-dsp-48-s32) (or (and (ifield f-dsp-48-u16) #xffff)
- (and (sll (ifield f-dsp-64-u16) 16) #xffff0000)))
+ (sll (and (ifield f-dsp-64-u16) #xffff) 16)))
)
)
@@ -827,7 +827,7 @@
(set (ifield f-dsp-16-s8) (sra INT (ifield f-bitbase32-16-s11-unprefixed) 3))
)
(sequence () ; extract
- (set (ifield f-bitbase32-16-s11-unprefixed) (or (sll (ifield f-dsp-16-s8) 3)
+ (set (ifield f-bitbase32-16-s11-unprefixed) (or (mul (ifield f-dsp-16-s8) 8)
(ifield f-bitno32-unprefixed)))
)
)
@@ -885,7 +885,7 @@
(set (ifield f-dsp-24-s8) (sra INT (ifield f-bitbase32-24-s11-prefixed) 3))
)
(sequence () ; extract
- (set (ifield f-bitbase32-24-s11-prefixed) (or (sll (ifield f-dsp-24-s8) 3)
+ (set (ifield f-bitbase32-24-s11-prefixed) (or (mul (ifield f-dsp-24-s8) 8)
(ifield f-bitno32-prefixed)))
)
)
@@ -913,7 +913,7 @@
)
(sequence () ; extract
(set (ifield f-bitbase32-24-s19-prefixed) (or (sll (ifield f-dsp-24-u8) 3)
- (or (sll (ifield f-dsp-32-s8) 11)
+ (or (mul (ifield f-dsp-32-s8) 2048)
(ifield f-bitno32-prefixed))))
)
)
@@ -1075,7 +1075,7 @@
(indices keyword "" (("r2r0" 0) ("r3r1" 1)))
(get (index) (or SI
(and (reg h-gr index) #xffff)
- (and (sll (reg h-gr (add index 2)) 16) #xffff0000)))
+ (sll (and (reg h-gr (add index 2)) #xffff) 16)))
(set (index newval) (sequence ()
(set (reg h-gr index) (and newval #xffff))
(set (reg h-gr (add index 2)) (srl newval 16)))))
--
Alan Modra
Australia Development Lab, IBM
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