From c578c495bb12b3b558e89b6b304a1b92756c544e Mon Sep 17 00:00:00 2001
From: George Koehler <xkernigh@netscape.net>
Date: Sat, 11 Feb 2017 18:00:56 -0500
Subject: [PATCH] Edit PowerPC assembly for .and, .cms, .ior, .xor, .zer

Remove one addi instruction from some loops.  These loops had
increased 2 pointers, they now increase 1 index.  I must initialize
the index, so I add "li r6, 0" before each loop.

Change .zer to use subf instead of neg, add.

Change .xor to take the size on the real stack, as .and and .or have
done since 81c677d.
---
 mach/powerpc/libem/and.s | 24 +++++++++++-------------
 mach/powerpc/libem/cms.s | 21 ++++++++++-----------
 mach/powerpc/libem/ior.s | 24 +++++++++++-------------
 mach/powerpc/libem/xor.s | 24 ++++++++++++------------
 mach/powerpc/libem/zer.s | 18 ++++++++----------
 mach/powerpc/ncg/table   | 12 +++++++-----
 6 files changed, 59 insertions(+), 64 deletions(-)

diff --git a/mach/powerpc/libem/and.s b/mach/powerpc/libem/and.s
index cb4e1e54a..cf5feee4d 100644
--- a/mach/powerpc/libem/and.s
+++ b/mach/powerpc/libem/and.s
@@ -5,20 +5,18 @@
 
 .define .and
 .and:
-	lwz r3, 0 (sp)      ! r3 = size
-	addi sp, sp, 4
-
-	mr	r4, sp			! r4 = ptr to set a
-	add	r5, sp, r3		! r5 = ptr to set b
-	srwi	r6, r3, 2
-	mtspr	ctr, r6			! ctr = r3 / 4
+	lwz	r3, 0(sp)		! r3 = size
+	srwi	r7, r3, 2
+	mtspr	ctr, r7			! ctr = size / 4
+	addi	r4, sp, 4		! r4 = ptr to set a
+	add	r5, r4, r3		! r5 = ptr to set b
+	li	r6, 0			! r6 = index
 1:
-	lwz	r7, 0(r4)
-	lwz	r8, 0(r5)
+	lwzx	r7, r4, r6
+	lwzx	r8, r5, r6
 	and	r8, r7, r8		! intersection of words
-	stw	r8, 0(r5)
-	addi	r4, r4, 4
-	addi	r5, r5, 4
+	stwx	r8, r5, r6
+	addi	r6, r6, 4
 	bdnz	1b			! loop ctr times
-	add	sp, sp, r3
+	mr	sp, r5
 	blr
diff --git a/mach/powerpc/libem/cms.s b/mach/powerpc/libem/cms.s
index 30aaccd20..5bcd3106d 100644
--- a/mach/powerpc/libem/cms.s
+++ b/mach/powerpc/libem/cms.s
@@ -7,24 +7,23 @@
 
 .define .cms
 .cms:
+	srwi	r7, r3, 2
+	mtspr	ctr, r7			! ctr = size / 4
 	mr	r4, sp			! r4 = ptr to set a
 	add	r5, sp, r3		! r5 = ptr to set b
-	mr	r6, r3			! r6 = size
-	srwi	r3, r3, 2
-	mtspr	ctr, r3			! ctr = size / 4
+	li	r6, 0			! r6 = index
+	add	r9, r5, r3		! r9 = future sp
 1:
-	lwz	r7, 0(r4)
-	lwz	r8, 0(r5)
+	lwzx	r7, r4, r6
+	lwzx	r8, r5, r6
 	cmpw	cr0, r7, r8		! compare words in sets
-	addi	r4, r4, 4
-	addi	r5, r5, 4
+	addi	r6, r6, 4
 	bne	cr0, 2f			! branch if not equal
 	bdnz	1b			! loop ctr times
-	addi	r3, r0, 0		! equal: return 0
+	li	r3, 0			! equal: return 0
 	b	3f
 2:
-	addi	r3, r0, 1		! not equal: return 1
+	li	r3, 1			! not equal: return 1
 3:
-	slwi	r6, r6, 1		! r6 = size * 2
-	add	sp, sp, r6		! remove sets from stack
+	mr	sp, r9			! remove sets from stack
 	blr
diff --git a/mach/powerpc/libem/ior.s b/mach/powerpc/libem/ior.s
index e6cd1844e..b4b0b3fae 100644
--- a/mach/powerpc/libem/ior.s
+++ b/mach/powerpc/libem/ior.s
@@ -5,20 +5,18 @@
 
 .define .ior
 .ior:
-	lwz r3, 0 (sp)
-	addi sp, sp, 4
-
-	mr	r4, sp			! r4 = ptr to set a
-	add	r5, sp, r3		! r5 = ptr to set b
-	srwi	r6, r3, 2
-	mtspr	ctr, r6			! ctr = r3 / 4
+	lwz	r3, 0(sp)		! r3 = size
+	srwi	r7, r3, 2
+	mtspr	ctr, r7			! ctr = size / 4
+	addi	r4, sp, 4		! r4 = ptr to set a
+	add	r5, r4, r3		! r5 = ptr to set b
+	li	r6, 0			! r6 = index
 1:
-	lwz	r7, 0(r4)
-	lwz	r8, 0(r5)
+	lwzx	r7, r4, r6
+	lwzx	r8, r5, r6
 	or	r8, r7, r8		! union of words
-	stw	r8, 0(r5)
-	addi	r4, r4, 4
-	addi	r5, r5, 4
+	stwx	r8, r5, r6
+	addi	r6, r6, 4
 	bdnz	1b			! loop ctr times
-	add	sp, sp, r3
+	mr	sp, r5
 	blr
diff --git a/mach/powerpc/libem/xor.s b/mach/powerpc/libem/xor.s
index acb02a032..6dc4e7afc 100644
--- a/mach/powerpc/libem/xor.s
+++ b/mach/powerpc/libem/xor.s
@@ -1,22 +1,22 @@
 .sect .text
 
 ! Set symmetric difference.
-!  Stack: ( b a -- a/b )
-!  With r3 = size of set
+!  Stack: ( b a size -- a/b )
 
 .define .xor
 .xor:
-	mr	r4, sp			! r4 = ptr to set a
-	add	r5, sp, r3		! r5 = ptr to set b
-	srwi	r6, r3, 2
-	mtspr	ctr, r6			! ctr = r3 / 4
+	lwz	r3, 0(sp)		! r3 = size
+	srwi	r7, r3, 2
+	mtspr	ctr, r7			! ctr = size / 4
+	addi	r4, sp, 4		! r4 = ptr to set a
+	add	r5, r4, r3		! r5 = ptr to set b
+	li	r6, 0			! r6 = index
 1:
-	lwz	r7, 0(r4)
-	lwz	r8, 0(r5)
+	lwzx	r7, r4, r6
+	lwzx	r8, r5, r6
 	xor	r8, r7, r8		! symmetric difference of words
-	stw	r8, 0(r5)
-	addi	r4, r4, 4
-	addi	r5, r5, 4
+	stwx	r8, r5, r6
+	addi	r6, r6, 4
 	bdnz	1b			! loop ctr times
-	add	sp, sp, r3
+	mr	sp, r5
 	blr
diff --git a/mach/powerpc/libem/zer.s b/mach/powerpc/libem/zer.s
index a47a150cc..d35744bba 100644
--- a/mach/powerpc/libem/zer.s
+++ b/mach/powerpc/libem/zer.s
@@ -5,17 +5,15 @@
 
 .define .zer
 .zer:
-	lwz     r3, 0(sp)
-	addi    sp, sp, 4
-
-	srwi	r7, r3, 2
-	li	r4, 0			! r4 = zero
-	neg	r5, r3
-	add	sp, sp, r5		! allocate set
-	mr	r6, sp			! r6 = ptr to set
-	mtspr	ctr, r7			! ctr = r3 / 4
+	lwz	r3, 0(sp)		! r3 = size
+	srwi	r5, r3, 2
+	mtspr	ctr, r5			! ctr = word size - 4
+	li	r4, 0			! r4 = 0
+	addi	sp, sp, 4
+	subf	sp, r3, sp		! sp = ptr to new set
+	li	r6, 0			! r6 = index
 1:
-	stw	r4, 0(r6)		! store zero in set
+	stwx	r4, sp, r6		! store zero in set
 	addi	r6, r6, 4
 	bdnz	1b			! loop ctr times
 	blr
diff --git a/mach/powerpc/ncg/table b/mach/powerpc/ncg/table
index 24822482c..1ba20a85e 100644
--- a/mach/powerpc/ncg/table
+++ b/mach/powerpc/ncg/table
@@ -1374,11 +1374,13 @@ PATTERNS
 			yields {XOR_RC, %2, lo(%1.val)}
 
 	pat xor defined($1)                /* XOR set */
-		with STACK
-			kills ALL
-			gen
-				move {CONST, $1}, R3
-				bl {LABEL, ".xor"}
+		leaving
+			loc $1
+			cal ".xor"
+
+	pat xor !defined($1)
+		leaving
+			cal ".xor"
 
 	pat com $1==INT32                  /* NOT word */
 		with AND_RR