scc

Simple C99 Compiler
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commit 9d132dc59173787dd773ce0e82b55bc4e1c1dffc
parent 2f6992e581ba599c2bcd14a04013b335269a542a
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Mon, 16 Mar 2015 09:25:04 +0000

Rewrite add code generation

We begin to be near of something functional

Diffstat:
cc2/cc2.h | 2++
cc2/cgen.c | 153+++++++++++++++++++++++++++++++++++++++++++++++++++++++++----------------------
cc2/code.c | 2++
3 files changed, 115 insertions(+), 42 deletions(-)

diff --git a/cc2/cc2.h b/cc2/cc2.h @@ -11,6 +11,7 @@ #define MEM 'T' #define PAR 'P' #define CONST '#' +#define PUSHED 'S' #define INDEX 'I' #define LABEL 'L' #define OADD '+' @@ -58,6 +59,7 @@ struct symbol { bool extrn : 1; char type; unsigned short id; + uint8_t reg; union { struct { Type type; diff --git a/cc2/cgen.c b/cc2/cgen.c @@ -117,15 +117,13 @@ allocreg(Node *np) } static void -move(Node *np) +moveto(Node *np, uint8_t reg) { Symbol *sym; - char reg; - - reg = allocreg(np); switch (np->op) { case AUTO: + case CONST: sym = np->u.sym; switch (np->type.size) { case 1: @@ -144,9 +142,50 @@ move(Node *np) default: abort(); } - /* TODO: Update symbol if necessary */ np->op = REG; - np->u.reg = reg; + sym->reg = np->u.reg = reg; +} + +static void +move(Node *np) +{ + moveto(np, allocreg(np)); +} + +static void +push(Node *np) +{ + code(PUSH, NULL, np); + np->op = PUSHED; +} + +static void +accum(Node *np) +{ + switch (np->type.size) { + case 1: + if (reguse[A]) + push(reguse[A]); + moveto(np, A); + break; + case 2: + if (reguse[H] || reguse[L]) + push(&reg_HL); + moveto(np, HL); + break; + case 4: + case 8: + abort(); + } +} + +static void +index(Node *np) +{ + if (reguse[H] || reguse[L]) + push(&reg_HL); + code(MOV, &reg_HL, np); + np->op = INDEX; } static void @@ -161,38 +200,71 @@ conmute(Node *np) } static void -add(Node *np, Node *lp, Node *rp) +add(Node *np) { + Node *lp = np->left, *rp = np->right; + + if (rp->op == REG || lp->op == CONST) { + conmute(np); + lp = np->left; + rp = np->right; + } switch (np->type.size) { case 1: - if (rp->u.reg == A) { - conmute(np); - lp = np->left; - rp = np->right; - } else if (lp->u.reg != A) { - /* TODO: Move A to variable */ - code(PUSH, NULL, lp); - code(LDL, regs[A], lp); + switch (lp->op) { + case PAR: + case AUTO: + switch (rp->op) { + case MEM: + index(rp); + case PAR: + case AUTO: + case CONST: + accum(lp); + break; + default: + abort(); + } + break; + case MEM: + if (reguse[A]) { + switch (rp->op) { + case PAR: + case AUTO: + case CONST: + break; + case MEM: + index(rp); + goto add_A; + default: + abort(); + } + } + accum(lp); + break; + case REG: + if (lp->u.reg != A) + moveto(lp, A); + switch (rp->op) { + case REG: + case AUTO: + case PAR: + case CONST: + case MEM: + break; + default: + abort(); + } + break; + default: + abort(); } - code(ADD, regs[A], rp); + add_A: + code(ADD, lp, rp); np->op = REG; np->u.reg = A; break; case 2: - if (rp->u.reg == HL || rp->u.reg == IY) { - conmute(np); - lp = np->left; - rp = np->right; - } else if (lp->u.reg != HL && lp->u.reg != IY) { - /* TODO: Move HL to variable */ - code(PUSH, NULL, lp); - code(LDL, regs[L], lp); - code(LDH, regs[H], lp); - } - code(ADD, lp, rp); - np->op = REG; - np->u.reg = lp->u.reg; - break; case 4: case 8: abort(); @@ -200,13 +272,15 @@ add(Node *np, Node *lp, Node *rp) } static void -assign(Node *np, Node *lp, Node *rp) +assign(Node *np) { + Node *lp = np->left, *rp = np->right; + switch (np->type.size) { case 1: switch (lp->op) { case AUTO: - code(LDL, rp, lp); + code(LDL, lp, rp); break; case REG: case MEM: @@ -220,7 +294,7 @@ assign(Node *np, Node *lp, Node *rp) } -static void (*opnodes[])(Node *, Node *, Node *) = { +static void (*opnodes[])(Node *) = { [OADD] = add, [OASSIG] = assign }; @@ -229,20 +303,15 @@ static void cgen(Node *np, Node *parent) { Node *lp, *rp; - TINT imm; if (!np) return; - lp = np->left; - rp = np->right; - if (np->addable >= ADDABLE) { - if (parent && parent->op == OASSIG) - return; - move(np); + if (np->addable >= ADDABLE) return; - } + lp = np->left; + rp = np->right; if (!lp) { cgen(rp, np); } else if (!rp) { @@ -257,7 +326,7 @@ cgen(Node *np, Node *parent) cgen(q, np); } - (*opnodes[np->op])(np, lp, rp); + (*opnodes[np->op])(np); } static Node * diff --git a/cc2/code.c b/cc2/code.c @@ -100,6 +100,8 @@ addr(char op, Node *np, Addr *addr) case MEM: addr->u.sym = np->u.sym; break; + case INDEX: + break; default: abort(); }