From fbe55325ddce51a7fc099e1efb0d326e7a2e1ed8 Mon Sep 17 00:00:00 2001
From: Ch1n-ch1nless <aleksandrov.oa.work@gmail.com>
Date: Thu, 21 Aug 2025 20:09:59 +0300
Subject: cmd/compile: replace conditions to CCMP instructions on ARM64

This change introduces a new SSA pass that converts conditionals
with logical AND into CMP/CCMP instruction sequences on ARM64.

Fixes #71268

Change-Id: I3eba9c05b88ed6eb70350d30f6e805e6a4dddbf1
Reviewed-on: https://go-review.googlesource.com/c/go/+/698099
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
---
 test/codegen/comparisons.go | 44 ++++++++++++++++++++++++++++++++++++++------
 1 file changed, 38 insertions(+), 6 deletions(-)

(limited to 'test/codegen')

diff --git a/test/codegen/comparisons.go b/test/codegen/comparisons.go
index 330497c656..43b95646eb 100644
--- a/test/codegen/comparisons.go
+++ b/test/codegen/comparisons.go
@@ -462,7 +462,7 @@ func CmpToZero_ex5(e, f int32, u uint32) int {
 
 func UintLtZero(a uint8, b uint16, c uint32, d uint64) int {
 	// amd64: -`(TESTB|TESTW|TESTL|TESTQ|JCC|JCS)`
-	// arm64: -`(CMPW|CMP|BHS|BLO)`
+	// arm64: -`(CMPW|CMP|CCMP|CCMPW|BHS|BLO)`
 	if a < 0 || b < 0 || c < 0 || d < 0 {
 		return 1
 	}
@@ -471,7 +471,7 @@ func UintLtZero(a uint8, b uint16, c uint32, d uint64) int {
 
 func UintGeqZero(a uint8, b uint16, c uint32, d uint64) int {
 	// amd64: -`(TESTB|TESTW|TESTL|TESTQ|JCS|JCC)`
-	// arm64: -`(CMPW|CMP|BLO|BHS)`
+	// arm64: -`(CMPW|CMP|CCMP|CCMPW|BLO|BHS)`
 	if a >= 0 || b >= 0 || c >= 0 || d >= 0 {
 		return 1
 	}
@@ -479,7 +479,7 @@ func UintGeqZero(a uint8, b uint16, c uint32, d uint64) int {
 }
 
 func UintGtZero(a uint8, b uint16, c uint32, d uint64) int {
-	// arm64: `(CBN?ZW)`, `(CBN?Z[^W])`, -`(CMPW|CMP|BLS|BHI)`
+	// arm64: `(CMPW|CMP|CCMP|CCMPW|BNE|BEQ)`
 	if a > 0 || b > 0 || c > 0 || d > 0 {
 		return 1
 	}
@@ -487,7 +487,7 @@ func UintGtZero(a uint8, b uint16, c uint32, d uint64) int {
 }
 
 func UintLeqZero(a uint8, b uint16, c uint32, d uint64) int {
-	// arm64: `(CBN?ZW)`, `(CBN?Z[^W])`, -`(CMPW|CMP|BHI|BLS)`
+	// arm64: `(CMPW|CMP|CCMP|CCMPW|BNE|BEQ)`
 	if a <= 0 || b <= 0 || c <= 0 || d <= 0 {
 		return 1
 	}
@@ -495,7 +495,7 @@ func UintLeqZero(a uint8, b uint16, c uint32, d uint64) int {
 }
 
 func UintLtOne(a uint8, b uint16, c uint32, d uint64) int {
-	// arm64: `(CBN?ZW)`, `(CBN?Z[^W])`, -`(CMPW|CMP|BHS|BLO)`
+	// arm64: `(CMPW|CMP|CCMP|CCMPW|BNE|BEQ)`
 	if a < 1 || b < 1 || c < 1 || d < 1 {
 		return 1
 	}
@@ -503,13 +503,45 @@ func UintLtOne(a uint8, b uint16, c uint32, d uint64) int {
 }
 
 func UintGeqOne(a uint8, b uint16, c uint32, d uint64) int {
-	// arm64: `(CBN?ZW)`, `(CBN?Z[^W])`, -`(CMPW|CMP|BLO|BHS)`
+	// arm64: `(CMPW|CMP|CCMP|CCMPW|BNE|BEQ)`
 	if a >= 1 || b >= 1 || c >= 1 || d >= 1 {
 		return 1
 	}
 	return 0
 }
 
+func ConditionalCompareUint8(a, b uint8) int {
+	// arm64:"CCMPW EQ, R[0-9]+, [$]1, [$]0"
+	if a == 1 && b == 1 {
+		return 1
+	}
+	return 0
+}
+
+func ConditionalCompareInt16(a, b int16) int {
+	// arm64:"CCMPW LE, R[0-9]+, R[0-9]+, [$]4"
+	if a > 3 || a == b {
+		return 1
+	}
+	return 0
+}
+
+func ConditionalCompareUint32(a, b uint32) int {
+	// arm64:"CCMPW LO, R[0-9]+, [$]28, [$]2"
+	if a > b && a < 28 {
+		return 1
+	}
+	return 0
+}
+
+func ConditionalCompareInt64(a, b int64) int {
+	// arm64:"CCMP GT, R[0-9]+, R[0-9]+, [$]0"
+	if a <= 16 || a != b {
+		return 1
+	}
+	return 0
+}
+
 func CmpToZeroU_ex1(a uint8, b uint16, c uint32, d uint64) int {
 	// wasm:"I64Eqz"-"I64LtU"
 	if 0 < a {
-- 
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