From b9eafdb190064326075109ebae8d1d3887b0b45c Mon Sep 17 00:00:00 2001
From: Alexander Richardson <alexrichardson@google.com>
Date: Mon, 26 Aug 2024 02:22:07 -0700
Subject: [PATCH] arch-arm: Fix implicit int-to-float conversion in VCMP
 (#1326)

Explicitly convert to float/double to fix compiler warnings that I have
turned on locally. It might make sense to make use of fplib functions to
be portable across different host float formats but something as simple
as comparison against zero should be safe.

Change-Id: I96c6ee7c5497fece11be07234ff80ff86e7555e2
---
 src/arch/arm/isa/insts/fp.isa | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/arch/arm/isa/insts/fp.isa b/src/arch/arm/isa/insts/fp.isa
index 55ecb93466..aaf5d72b68 100644
--- a/src/arch/arm/isa/insts/fp.isa
+++ b/src/arch/arm/isa/insts/fp.isa
@@ -1360,13 +1360,12 @@ let {{
     vcmpZeroSCode = vfpEnabledCheckCode + '''
         FPSCR fpscr = (FPSCR) FpscrExc;
         vfpFlushToZero(fpscr, FpDest);
-        // This only handles imm == 0 for now.
-        assert(imm == 0);
-        if (FpDest == imm) {
+        assert(imm == 0); // immediate must be zero.
+        if (FpDest == 0.0f) {
             fpscr.n = 0; fpscr.z = 1; fpscr.c = 1; fpscr.v = 0;
-        } else if (FpDest < imm) {
+        } else if (FpDest < 0.0f) {
             fpscr.n = 1; fpscr.z = 0; fpscr.c = 0; fpscr.v = 0;
-        } else if (FpDest > imm) {
+        } else if (FpDest > 0.0f) {
             fpscr.n = 0; fpscr.z = 0; fpscr.c = 1; fpscr.v = 0;
         } else {
             const uint32_t qnan = 0x7fc00000;
@@ -1388,16 +1387,15 @@ let {{
     exec_output += PredOpExecute.subst(vcmpZeroSIop);
 
     vcmpZeroDCode = vfpEnabledCheckCode + '''
-        // This only handles imm == 0 for now.
-        assert(imm == 0);
         double cDest = dbl(FpDestP0_uw, FpDestP1_uw);
         FPSCR fpscr = (FPSCR) FpscrExc;
         vfpFlushToZero(fpscr, cDest);
-        if (cDest == imm) {
+        assert(imm == 0); // immediate must be zero.
+        if (cDest == 0.0) {
             fpscr.n = 0; fpscr.z = 1; fpscr.c = 1; fpscr.v = 0;
-        } else if (cDest < imm) {
+        } else if (cDest < 0.0) {
             fpscr.n = 1; fpscr.z = 0; fpscr.c = 0; fpscr.v = 0;
-        } else if (cDest > imm) {
+        } else if (cDest > 0.0) {
             fpscr.n = 0; fpscr.z = 0; fpscr.c = 1; fpscr.v = 0;
         } else {
             const uint64_t qnan = 0x7ff8000000000000ULL;
@@ -1471,11 +1469,12 @@ let {{
     vcmpeZeroSCode = vfpEnabledCheckCode + '''
         FPSCR fpscr = (FPSCR) FpscrExc;
         vfpFlushToZero(fpscr, FpDest);
-        if (FpDest == imm) {
+        assert(imm == 0); // immediate must be zero.
+        if (FpDest == 0.0f) {
             fpscr.n = 0; fpscr.z = 1; fpscr.c = 1; fpscr.v = 0;
-        } else if (FpDest < imm) {
+        } else if (FpDest < 0.0f) {
             fpscr.n = 1; fpscr.z = 0; fpscr.c = 0; fpscr.v = 0;
-        } else if (FpDest > imm) {
+        } else if (FpDest > 0.0f) {
             fpscr.n = 0; fpscr.z = 0; fpscr.c = 1; fpscr.v = 0;
         } else {
             fpscr.ioc = 1;
@@ -1496,11 +1495,12 @@ let {{
         double cDest = dbl(FpDestP0_uw, FpDestP1_uw);
         FPSCR fpscr = (FPSCR) FpscrExc;
         vfpFlushToZero(fpscr, cDest);
-        if (cDest == imm) {
+        assert(imm == 0); // immediate must be zero.
+        if (cDest == 0.0) {
             fpscr.n = 0; fpscr.z = 1; fpscr.c = 1; fpscr.v = 0;
-        } else if (cDest < imm) {
+        } else if (cDest < 0.0) {
             fpscr.n = 1; fpscr.z = 0; fpscr.c = 0; fpscr.v = 0;
-        } else if (cDest > imm) {
+        } else if (cDest > 0.0) {
             fpscr.n = 0; fpscr.z = 0; fpscr.c = 1; fpscr.v = 0;
         } else {
             fpscr.ioc = 1;