diff options
Diffstat (limited to 'chapter21/src')
3 files changed, 16 insertions, 4 deletions
diff --git a/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/arm/OrIARM.java b/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/arm/OrIARM.java index 68550926..3f72f026 100644 --- a/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/arm/OrIARM.java +++ b/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/arm/OrIARM.java @@ -14,7 +14,7 @@ public class OrIARM extends MachConcreteNode implements MachNode { @Override public String op() { return "ori"; } @Override public RegMask regmap(int i) { return arm.RMASK; } @Override public RegMask outregmap() { return arm.RMASK; } - @Override public void encoding( Encoding enc ) { arm.imm_inst(enc,this,170,_imm); } + @Override public void encoding( Encoding enc ) { arm.imm_inst(enc,this,0xC8,_imm); } // General form: "ori rd = rs1 | imm" @Override public void asm(CodeGen code, SB sb) { sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" | #").p(_imm); diff --git a/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/arm/arm.java b/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/arm/arm.java index 6fc0afec..add609fc 100644 --- a/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/arm/arm.java +++ b/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/arm/arm.java @@ -164,8 +164,19 @@ public class arm extends Machine { return ti.isConstant() && ((ti.value()<<52)>>52) == ti.value(); } + + // Can we encode this in ARM's 12-bit LOGICAL immediate form? + // Some combination of shifted bit-masks. + private static int imm12Logical(TypeInteger ti) { + if( !ti.isConstant() ) return -1; + // TODO: THE REAL THING + // INVARIANT: always a positive thing + return -1; + } + // sh is encoded in opcdoe public static int imm_inst(int opcode, int imm12, int rn, int rd) { + assert opcode >=0 && imm12 >= 0 && rn >=0 && rd>=0; // Caller zeros high order bits return (opcode << 22) | (imm12 << 10) | (rn << 5) | rd; } public static void imm_inst(Encoding enc, Node n, int opcode, int imm12) { @@ -477,8 +488,9 @@ public class arm extends Machine { } private Node or(OrNode or) { - return or.in(2) instanceof ConstantNode off && off._con instanceof TypeInteger ti && imm12(ti) - ? new OrIARM(or, (int)ti.value()) + int imm12; + return or.in(2) instanceof ConstantNode off && off._con instanceof TypeInteger ti && (imm12 = imm12Logical(ti)) != -1 + ? new OrIARM(or, imm12) : new OrARM(or); } diff --git a/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/riscv/RetRISC.java b/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/riscv/RetRISC.java index 42f34d85..9f89f983 100644 --- a/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/riscv/RetRISC.java +++ b/chapter21/src/main/java/com/seaofnodes/simple/node/cpus/riscv/RetRISC.java @@ -20,7 +20,7 @@ public class RetRISC extends ReturnNode implements MachNode{ @Override public RegMask regmap(int i) { return riscv.retMask(_fun.sig(),i); } @Override public RegMask outregmap() { return null; } @Override public void encoding( Encoding enc ) { - short rpc = enc.reg(this); + short rpc = enc.reg(rpc()); int body = riscv.i_type(0x67, riscv.ZERO, 0, rpc, 0); enc.add4(body); } |