internal/bytealg: port bytealg functions to reg ABI on ppc64x

This adds support for the reg ABI to the bytes functions for
ppc64/ppc64le. These are initially under control of the
GOEXPERIMENT macro until all changes are in.

Change-Id: Id82f31056af8caa8541e27c6735f6b815a5dbf5a
Reviewed-on: https://go-review.googlesource.com/c/go/+/351190
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

3 files changed, 95 insertions, 20 deletions

diff --git a/src/internal/bytealg/compare_ppc64x.s b/src/internal/bytealg/compare_ppc64x.s
index 83444fa826..390a72688b 100644
--- a/src/internal/bytealg/compare_ppc64x.s
+++ b/src/internal/bytealg/compare_ppc64x.s
@@ -8,64 +8,99 @@
 #include "go_asm.h"
 #include "textflag.h"
 
-TEXT ·Compare(SB),NOSPLIT|NOFRAME,$0-56
+TEXT ·Compare<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-56
+#ifdef GOEXPERIMENT_regabiargs
+// incoming:
+// R3 a addr -> R5
+// R4 a len  -> R3
+// R5 a cap unused
+// R6 b addr -> R6
+// R7 b len  -> R4
+// R8 b cap unused
+	MOVD	R3, R5
+	MOVD	R4, R3
+	MOVD	R7, R4
+#else
 	MOVD	a_base+0(FP), R5
 	MOVD	b_base+24(FP), R6
 	MOVD	a_len+8(FP), R3
-	CMP	R5,R6,CR7
 	MOVD	b_len+32(FP), R4
 	MOVD	$ret+48(FP), R7
+#endif
+	CMP     R5,R6,CR7
 	CMP	R3,R4,CR6
 	BEQ	CR7,equal
-
 #ifdef	GOARCH_ppc64le
 	BR	cmpbodyLE<>(SB)
 #else
 	BR      cmpbodyBE<>(SB)
 #endif
-
 equal:
 	BEQ	CR6,done
 	MOVD	$1, R8
 	BGT	CR6,greater
 	NEG	R8
-
 greater:
+#ifdef GOEXPERIMENT_regabiargs
+	MOVD	R8, R3
+#else
 	MOVD	R8, (R7)
+#endif
 	RET
-
 done:
+#ifdef GOEXPERIMENT_regabiargs
+	MOVD	$0, R3
+#else
 	MOVD	$0, (R7)
+#endif
 	RET
 
-TEXT runtime·cmpstring(SB),NOSPLIT|NOFRAME,$0-40
+TEXT runtime·cmpstring<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-40
+#ifdef GOEXPERIMENT_regabiargs
+// incoming:
+// R3 a addr -> R5
+// R4 a len  -> R3
+// R5 b addr -> R6
+// R6 b len  -> R4
+	MOVD	R6, R7
+	MOVD	R5, R6
+	MOVD	R3, R5
+	MOVD	R4, R3
+	MOVD	R7, R4
+#else
 	MOVD	a_base+0(FP), R5
 	MOVD	b_base+16(FP), R6
 	MOVD	a_len+8(FP), R3
-	CMP	R5,R6,CR7
 	MOVD	b_len+24(FP), R4
 	MOVD	$ret+32(FP), R7
+#endif
+	CMP     R5,R6,CR7
 	CMP	R3,R4,CR6
 	BEQ	CR7,equal
-
 #ifdef	GOARCH_ppc64le
 	BR	cmpbodyLE<>(SB)
 #else
 	BR      cmpbodyBE<>(SB)
 #endif
-
 equal:
 	BEQ	CR6,done
 	MOVD	$1, R8
 	BGT	CR6,greater
 	NEG	R8
-
 greater:
+#ifdef GOEXPERIMENT_regabiargs
+	MOVD	R8, R3
+#else
 	MOVD	R8, (R7)
+#endif
 	RET
 
 done:
+#ifdef GOEXPERIMENT_regabiargs
+	MOVD	$0, R3
+#else
 	MOVD	$0, (R7)
+#endif
 	RET
 
 // Do an efficient memcmp for ppc64le
@@ -73,7 +108,7 @@ done:
 // R4 = b len
 // R5 = a addr
 // R6 = b addr
-// R7 = addr of return value
+// R7 = addr of return value if not regabi
 TEXT cmpbodyLE<>(SB),NOSPLIT|NOFRAME,$0-0
 	MOVD	R3,R8		// set up length
 	CMP	R3,R4,CR2	// unequal?
@@ -168,14 +203,22 @@ cmpne:				// only here is not equal
 	BGT	greater		// here only if NE
 less:
 	MOVD	$-1,R3
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD	R3,(R7)		// return value if A < B
+#endif
 	RET
 equal:
+#ifdef GOEXPERIMENT_regabiargs
+	MOVD	$0, R3
+#else
 	MOVD	$0,(R7)		// return value if A == B
+#endif
 	RET
 greater:
 	MOVD	$1,R3
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD	R3,(R7)		// return value if A > B
+#endif
 	RET
 
 // Do an efficient memcmp for ppc64 (BE)
@@ -267,12 +310,20 @@ simple:
 	BC	12,9,greater	// 2nd len > 1st len
 less:
 	MOVD	$-1,R3
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD    R3,(R7)		// return value if A < B
+#endif
 	RET
 equal:
+#ifdef GOEXPERIMENT_regabiargs
+	MOVD	$0, R3
+#else
 	MOVD    $0,(R7)		// return value if A == B
+#endif
 	RET
 greater:
 	MOVD	$1,R3
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD	R3,(R7)		// return value if A > B
+#endif
 	RET
diff --git a/src/internal/bytealg/equal_ppc64x.s b/src/internal/bytealg/equal_ppc64x.s
index 5f0fea521b..d59154101a 100644
--- a/src/internal/bytealg/equal_ppc64x.s
+++ b/src/internal/bytealg/equal_ppc64x.s
@@ -9,33 +9,38 @@
 #include "textflag.h"
 
 // memequal(a, b unsafe.Pointer, size uintptr) bool
-TEXT runtime·memequal(SB),NOSPLIT|NOFRAME,$0-25
+TEXT runtime·memequal<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-25
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD    a+0(FP), R3
 	MOVD    b+8(FP), R4
 	MOVD    size+16(FP), R5
 	MOVD    $ret+24(FP), R10
-
+#endif
 	BR	memeqbody<>(SB)
 
 // memequal_varlen(a, b unsafe.Pointer) bool
-TEXT runtime·memequal_varlen(SB),NOSPLIT|NOFRAME,$0-17
+TEXT runtime·memequal_varlen<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-17
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD	a+0(FP), R3
 	MOVD	b+8(FP), R4
+	MOVD    $ret+16(FP), R10
+#endif
 	CMP	R3, R4
 	BEQ	eq
 	MOVD	8(R11), R5    // compiler stores size at offset 8 in the closure
-	MOVD    $ret+16(FP), R10
 	BR	memeqbody<>(SB)
 eq:
 	MOVD	$1, R3
+#ifndef GOEXPERIMENT_regabiargs
 	MOVB	R3, ret+16(FP)
+#endif
 	RET
 
 // Do an efficient memequal for ppc64
 // R3 = s1
 // R4 = s2
 // R5 = len
-// R10 = addr of return value (byte)
+// R10 = addr of return value (byte) when not regabi
 TEXT memeqbody<>(SB),NOSPLIT|NOFRAME,$0-0
 	MOVD    R5,CTR
 	CMP     R5,$8		// only optimize >=8
@@ -94,10 +99,16 @@ simple:
 	BNE	noteq
 	BR	equal
 noteq:
+#ifdef GOEXPERIMENT_regabiargs
+	MOVD	$0, R3
+#else
 	MOVB    $0, (R10)
+#endif
 	RET
 equal:
 	MOVD	$1, R3
+#ifndef GOEXPERIMENT_regabiargs
 	MOVB	R3, (R10)
+#endif
 	RET
 
diff --git a/src/internal/bytealg/indexbyte_ppc64x.s b/src/internal/bytealg/indexbyte_ppc64x.s
index 8e13c5a56e..27e1ad7e0d 100644
--- a/src/internal/bytealg/indexbyte_ppc64x.s
+++ b/src/internal/bytealg/indexbyte_ppc64x.s
@@ -8,20 +8,29 @@
 #include "go_asm.h"
 #include "textflag.h"
 
-TEXT ·IndexByte(SB),NOSPLIT|NOFRAME,$0-40
+TEXT ·IndexByte<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-40
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD	b_base+0(FP), R3	// R3 = byte array pointer
 	MOVD	b_len+8(FP), R4		// R4 = length
 	MOVBZ	c+24(FP), R5		// R5 = byte
 	MOVD	$ret+32(FP), R14	// R14 = &ret
+#else
+	MOVD	R6, R5
+#endif
 	BR	indexbytebody<>(SB)
 
-TEXT ·IndexByteString(SB),NOSPLIT|NOFRAME,$0-32
+TEXT ·IndexByteString<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-32
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD	s_base+0(FP), R3  // R3 = string
 	MOVD	s_len+8(FP), R4	  // R4 = length
 	MOVBZ	c+16(FP), R5	  // R5 = byte
 	MOVD	$ret+24(FP), R14  // R14 = &ret
+#endif
 	BR	indexbytebody<>(SB)
-
+// R3 = addr of string
+// R4 = len of string
+// R5 = byte to find
+// R14 = addr of return value when not regabi
 TEXT indexbytebody<>(SB),NOSPLIT|NOFRAME,$0-0
 	MOVD	R3,R17		// Save base address for calculating the index later.
 	RLDICR	$0,R3,$60,R8	// Align address to doubleword boundary in R8.
@@ -186,7 +195,9 @@ tail:
 
 notfound:
 	MOVD	$-1,R3
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD	R3,(R14)
+#endif
 	RET
 
 found:
@@ -229,7 +240,9 @@ found:
 
 return:
 	SUB	R17,R3
+#ifndef GOEXPERIMENT_regabiargs
 	MOVD	R3,(R14)
+#endif
 	RET
 
 found_qw_align: