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V850: Fixed multiply by immediate

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Multiply by immediate (mul imm9, reg2, reg3) used a signed token for the lower 5 bits of the immediate value imm9.
This resulted in any immediate value in which the 5th bit was set to be calculated incorrectly.

imm9 = 0x18 ( 0b000011000 )
OLD:    f8 0f 40 52        mul    -0x8, r1, r10
NEW:   f8 0f 40 52        mul    0x18, r1, r10

imm9 = -0xF0 ( 0b100010000 )
OLD:    f0 0f 60 52        mul    -0x10, r1, r10
NEW:   f0 0f 60 52        mul    -0xf0, r1, r10
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Cameron Taylor 2021-04-22 20:50:11 -04:00 • committed by GitHub
parent b57744d4e0
commit c8322ba9e7
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Ghidra/Processors/V850/data/languages/Instructions/Arithmetic.sinc
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@ -21,8 +21,8 @@
}
# MUL imm9, reg2, reg3 - rrrrr111111iiiii|wwwww01001IIII00
:mul imm9, R1115, R2731 is op0510=0x3F & s0004 & R1115; op2226=0x9 & op1617=0x0 & s1821 & R2731
[ imm9 = (s1821 << 5) | s0004; ]
:mul imm9, R1115, R2731 is op0510=0x3F & op0004 & R1115; op2226=0x9 & op1617=0x0 & s1821 & R2731
[ imm9 = (s1821 << 5) | op0004; ]
{
local res:8 = sext(R1115) * imm9;
R1115 = res:4;