From: David Given <dg@cowlark.com>
Date: Thu, 29 Sep 2016 17:58:02 +0000 (+0200)
Subject: You know what, the type inference stuff is a complete red herring. What this
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=a0131fdb479e664d86c941de5c416d02d8c554c1;p=ack.git

You know what, the type inference stuff is a complete red herring. What this
actually needs is a more intelligent register allocator. So, remove the type
inference.
---

diff --git a/mach/proto/mcg/ir.c b/mach/proto/mcg/ir.c
index 9d1dab112..4d61bddeb 100644
--- a/mach/proto/mcg/ir.c
+++ b/mach/proto/mcg/ir.c
@@ -106,12 +106,6 @@ static void print_expr(char k, const struct ir* ir)
     tracef(k, "%s", ir_data[ir->opcode].name);
     if (ir->size)
         tracef(k, "%d", ir->size);
-    if (ir->type)
-        tracef(k, ".%s",
-            ((ir->type == IRT_INT) ? "I" :
-             (ir->type == IRT_FLOAT) ? "F" :
-             (ir->type == IRT_ANY) ? "*" :
-             "?"));
     tracef(k, "(");
 
 	switch (ir->opcode)
diff --git a/mach/proto/mcg/ir.h b/mach/proto/mcg/ir.h
index f63272a6c..d38ecf1d5 100644
--- a/mach/proto/mcg/ir.h
+++ b/mach/proto/mcg/ir.h
@@ -8,7 +8,6 @@ struct ir
 	int id;
 	enum ir_opcode opcode;
 	int size;
-	enum ir_type type;
 	struct ir* left;
 	struct ir* right;
 	union
diff --git a/mach/proto/mcg/mcg.h b/mach/proto/mcg/mcg.h
index 8cf16f952..a836ecc2f 100644
--- a/mach/proto/mcg/mcg.h
+++ b/mach/proto/mcg/mcg.h
@@ -123,7 +123,6 @@ extern void pass_convert_stack_ops(struct procedure* proc);
 extern void pass_remove_dead_blocks(struct procedure* proc);
 extern void pass_eliminate_trivial_blocks(struct procedure* proc);
 extern void pass_instruction_selector(struct procedure* proc);
-extern void pass_type_inference(struct procedure* proc);
 
 extern void procedure_compile(struct procedure* proc);
 
diff --git a/mach/proto/mcg/pass_typeinference.c b/mach/proto/mcg/pass_typeinference.c
deleted file mode 100644
index a3a8335ee..000000000
--- a/mach/proto/mcg/pass_typeinference.c
+++ /dev/null
@@ -1,63 +0,0 @@
-#include "mcg.h"
-
-static enum ir_type search_for_type(struct ir* ir, enum ir_type desired)
-{
-	const struct ir_data* data;
-
-	if (ir->type != IRT_UNSET)
-		return ir->type;
-
-	data = &ir_data[ir->opcode];
-	if (ir->left)
-		ir->left->type = search_for_type(ir->left, data->lefttype);
-	if (ir->right)
-		ir->right->type = search_for_type(ir->right, data->righttype);
-	
-    switch (data->returntype)
-    {
-        case IRT_ANY:
-            if (desired == IRT_FLOAT)
-                ir->opcode++;
-            return desired;
-
-        case IRT_UNSET:
-            assert(!((data->lefttype == IRT_ANY) && (data->righttype == IRT_ANY)));
-            if (((data->lefttype == IRT_ANY) && (ir->left->type == IRT_FLOAT)) ||
-                ((data->righttype == IRT_ANY) && (ir->right->type == IRT_FLOAT)))
-            {
-                ir->opcode++;
-                return IRT_FLOAT;
-            }
-            if ((data->lefttype == IRT_ANY) && (ir->left->type == IRT_ANY))
-                ir->left->type = IRT_INT;
-            if ((data->righttype == IRT_ANY) && (ir->right->type == IRT_ANY))
-                ir->right->type = IRT_INT;
-            return IRT_INT;
-
-        default:
-            return data->returntype;
-	}
-}
-
-static void push_types_up(struct basicblock* bb)
-{
-	int i;
-
-	for (i=0; i<bb->irs.count; i++)
-	{
-		struct ir* ir = bb->irs.item[i];
-		ir->type = search_for_type(ir, ir->type);
-	}
-}
-
-void pass_type_inference(struct procedure* proc)
-{
-    int i;
-    
-	for (i=0; i<proc->blocks.count; i++)
-		push_types_up(proc->blocks.item[i]);
-}
-
-/* vim: set sw=4 ts=4 expandtab : */
-
-
diff --git a/mach/proto/mcg/procedure.c b/mach/proto/mcg/procedure.c
index 2adc74c0f..a27aeedf7 100644
--- a/mach/proto/mcg/procedure.c
+++ b/mach/proto/mcg/procedure.c
@@ -29,7 +29,6 @@ void procedure_compile(struct procedure* proc)
     pass_eliminate_trivial_blocks(proc);
     pass_remove_dead_blocks(proc);
     pass_convert_stack_ops(proc);
-    pass_type_inference(proc);
 
     print_blocks('2', proc);
 
diff --git a/mach/proto/mcg/table b/mach/proto/mcg/table
index 3348787c3..9bd39d4b5 100644
--- a/mach/proto/mcg/table
+++ b/mach/proto/mcg/table
@@ -174,4 +174,4 @@ PATTERNS
 
 	reg = value:CONST4
 		emit "ldr %reg, #$value"
-		cost 4;
+		cost 8;
diff --git a/util/mcgg/ir.dat b/util/mcgg/ir.dat
index 46be39408..3dd785b5c 100644
--- a/util/mcgg/ir.dat
+++ b/util/mcgg/ir.dat
@@ -1,92 +1,76 @@
 # Flags:
 #   S: has size (use in CONST1, CONST2, CONST4, CONST8 forms)
 #   V: has no size (use in JUMP, CJUMP, RET forms)
-#
-# Types:
-#   I, F: integer, float
-#   A: any (will be coerced to I or F during IR postprocessing)
-#
-# Any instruction with an A type must be followed by the corresponding F
-# version.
 
 # Simple terminals
-SA.. CONST
-SF.. CONSTF
-SA.. REG
-SF.. REGF
-SI.. LABEL
-SI.. BLOCK
-V... PAIR
-SA.. ANY
-SF.. ANYF
-S... LOCAL
-S... PHI
+S CONST
+S REG
+S LABEL
+S BLOCK
+V PAIR
+S ANY
+S LOCAL
+S PHI
 
 # Magic stack operations
-S.A. PUSH
-S.F. PUSHF
-SA.. POP
-SF.. POPF
+S PUSH
+S POP
 
 #... Memory operations
-SAI. LOAD
-SFI. LOADF
-S.IA STORE
-S.IF STOREF
+S LOAD
+S STORE
 
 # Arithemetic operations
-SIII ADD
-SIII SUB
-SIII MUL
-SIII DIV
-SIII MOD
-SIII NEG
+S ADD
+S SUB
+S MUL
+S DIV
+S MOD
+S NEG
 
-SFFF ADDF
-SFFF SUBF
-SFFF MULF
-SFFF DIVF
-SFFF NEGF
+S ADDF
+S SUBF
+S MULF
+S DIVF
+S NEGF
 
-SIII AND
-SIII OR
-SIII EOR
-SIII NOT
+S AND
+S OR
+S EOR
+S NOT
 
 # Conversions
-SIII CII1
-SIII CII2
-SIII CII4
-SIII CII8
+S CII1
+S CII2
+S CII4
+S CII8
 
-SIII CIU1
-SIII CIU2
-SIII CIU4
-SIII CIU8
+S CIU1
+S CIU2
+S CIU4
+S CIU8
 
 # Tristate comparisons
-SIII COMPARES
-SIII COMPAREU
+S COMPARES
+S COMPAREU
 
 # Boolean comparisons
-SIII IFEQ
-SIII IFLT
-SIII IFLE
+S IFEQ
+S IFLT
+S IFLE
 
 # Procedures
-VI.. CALL
+V CALL
 
 # Flow control --- these never return
-V.I. JUMP
-VIII CJUMPEQ
-VIII CJUMPLT
-VIII CJUMPLE
-V... RET
+V JUMP
+V CJUMPEQ
+V CJUMPLT
+V CJUMPLE
+V RET
  
 # Special
-SI.. STACKADJUST
-SA.. GETRET
-SF.. GETRETF
-S.A. SETRET
-S.F. SETRETF
+S STACKADJUST
+S GETRET
+S SETRET
 
diff --git a/util/mcgg/ircodes.h b/util/mcgg/ircodes.h
index 99dbae7bb..c5bbb9f2d 100644
--- a/util/mcgg/ircodes.h
+++ b/util/mcgg/ircodes.h
@@ -6,21 +6,10 @@ enum
 	IRF_SIZED = 1,
 };
 
-enum ir_type
-{
-	IRT_UNSET = 0,
-	IRT_INT,
-	IRT_FLOAT,
-	IRT_ANY
-};
-
 struct ir_data
 {
 	const char* name;
 	int flags;
-	enum ir_type returntype;
-	enum ir_type lefttype;
-	enum ir_type righttype;
 };
 
 extern const struct ir_data ir_data[];
diff --git a/util/mcgg/ircodes.sh b/util/mcgg/ircodes.sh
index e4d289da7..7c9917d12 100755
--- a/util/mcgg/ircodes.sh
+++ b/util/mcgg/ircodes.sh
@@ -25,13 +25,6 @@ awk -f - $in >$source << "EOF"
 		print "const struct ir_data ir_data[IR__COUNT] = {"
 	}
 
-	function char_to_type(c) {
-		if (c == "I") return "IRT_INT"
-		if (c == "F") return "IRT_FLOAT"
-		if (c == "A") return "IRT_ANY"
-		return "IRT_UNSET"
-	}
-
 	function char_to_flags(c) {
 		if (c == "S") return "IRF_SIZED"
 		return "0"
@@ -39,10 +32,7 @@ awk -f - $in >$source << "EOF"
 
 	/^ *[^# ]+/ {
 		printf("\t{ \"%s\", ", $2)
-		printf("%s, ", char_to_flags(substr($1, 1, 1)))
-		printf("%s, ", char_to_type(substr($1, 2, 1)))
-		printf("%s, ", char_to_type(substr($1, 3, 1)))
-		printf("%s", char_to_type(substr($1, 4, 1)))
+		printf("%s", char_to_flags(substr($1, 1, 1)))
 		printf(" },\n")
 	}