From ba349144651bc5b0ebe28aa38ac802a75ecaa0bb Mon Sep 17 00:00:00 2001
From: Paul Mackerras <paulus@ozlabs.org>
Date: Tue, 31 Aug 2021 11:45:57 +1000
Subject: [PATCH] tests/misc: Add a test for a load that hits two preceding
 stores

This checks that the store forwarding machinery in the dcache
correctly combines forwarded stores when they are partial stores
(i.e. only writing part of the doubleword, as for a byte store).

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 tests/misc/head.S           |  23 +++++++++++++++++++++++
 tests/misc/misc.c           |   8 ++++++++
 tests/test_misc.bin         | Bin 5740 -> 5804 bytes
 tests/test_misc.console_out |   1 +
 4 files changed, 32 insertions(+)

diff --git a/tests/misc/head.S b/tests/misc/head.S
index d490a61..9044c51 100644
--- a/tests/misc/head.S
+++ b/tests/misc/head.S
@@ -162,3 +162,26 @@ test_bdnzl:
 	li	%r3,0
 9:	mtlr	%r10
 	blr
+
+/* Test that a load that hits stores gets the correct data */
+	.global test_loadhitstore
+test_loadhitstore:
+	addi	%r5,%r1,-16
+	ld	%r0,0(%r5)
+	li	%r0,0
+	std	%r0,0(%r5)
+	li	%r6,0x66
+	li	%r7,0x77
+	.balign	64
+	nop
+	nop
+	nop
+	nop
+	stb	%r6,2(%r5)
+	stb	%r7,3(%r5)
+	ld	%r0,0(%r5)
+	sldi	%r6,%r6,16
+	sldi	%r7,%r7,24
+	or	%r7,%r6,%r7
+	subf	%r3,%r0,%r7
+	blr
diff --git a/tests/misc/misc.c b/tests/misc/misc.c
index 73745d9..3cc0300 100644
--- a/tests/misc/misc.c
+++ b/tests/misc/misc.c
@@ -15,6 +15,7 @@ extern long test_addpcis_2(void);
 extern long test_mfpvr(void);
 extern long test_mtpvr(void);
 extern long test_bdnzl(void);
+extern long test_loadhitstore(void);
 
 // i < 100
 void print_test_number(int i)
@@ -66,5 +67,12 @@ int main(void)
 	} else
 		puts(PASS);
 
+	print_test_number(6);
+	if (test_loadhitstore() != 0) {
+		fail = 1;
+		puts(FAIL);
+	} else
+		puts(PASS);
+
 	return fail;
 }
diff --git a/tests/test_misc.bin b/tests/test_misc.bin
index 2264686c06a630733a71d56de90ea1a1f3925baf..648ab184ab362a9a3c1ba0c554df4f1ceb96bb3e 100755
GIT binary patch
delta 549
zcmaE(vqpDA0%O33{|hY`7+7C0Fff4VA88B+EXo-k0ND%)3=B>{45AU3iQ(uBW`?IT
zKzg1uAFFtB@Oedr_3@eji-Z~lh6caQiHre!lLSm$CzK{z2rw}IxcFc3hb}XN2gs0X
zzyH-6Fw|RcG5nX`!k%0+kqIIm@S(oOfFaoeBvuO*vtmfFD4bj=V9e+_d98r7AO~ZU
z<NyCjHjE4ptY-kto;vv^Q1lA}s%Yk9RzZ288)%}IOq0z7<?8pK33EcNVg*{Y_TPW+
zneYF5L;R|&vjk1;T}Fsg*??*rfocyTsqH~iyAi6^fI-os;`ifv3!r+S)9Y;*fNoy^
zbo)f8f<F)m8<1EnR7~VQSTR^E6J`*SSSVD?2T9BkDwcvIrVACT0g3@V1q7RggxnYz
xGd4#GYcnwhOl}obmtOJf|NkS5Ksh%)13|~S`HW2NTzm{p_t_k|Cm$DG3IO!FypjL_

delta 399
zcmZ3Z`$lI&0^{b5jQ)I+4=@H!5-@QMC{4ByU|{@l@xS7aw@eHk3=9kj*M9%2H(;o@
z;9~eMzlA-yCJ-tf@S(oOfFaoeBxVa0vtmfFFq~W|V9dxld98r7;2nl0$N&G6Y#13H
zSVsWO4xM}xD0%`-RC6+`puEr;G|``olg$L>>L;KHpJaqMixp_q+JFDOXTJaM4RR&}
zgR)Kqn%cQgwFV4|78SoA*QWs0gPg+vbWQ@$IkixEjsFmFkXR;E%mE^1W&;uog$l+X
zDRhL2RUnD!Ld7O*_7w7GWL&X%rm!{><AljaMb)KW{QCdDg%RjfH$DSF$GZ89HC%iQ
PPWRayxfv$2i!B8J=c<aw

diff --git a/tests/test_misc.console_out b/tests/test_misc.console_out
index e59c03f..5296101 100644
--- a/tests/test_misc.console_out
+++ b/tests/test_misc.console_out
@@ -3,3 +3,4 @@ Test 02:PASS
 Test 03:PASS
 Test 04:PASS
 Test 05:PASS
+Test 06:PASS